Stop UK Lies and Corruption v The Information Commissioner & Anor

The appellant argued that the Commissioner’s approach bypassed a comprehensive review of the information requested and neglected the public interest test that should have been applied to each exemption. The appellant submitted that by failing to consider sections 24(1) and 31(1)(a), the decision lacked the depth and thoroughness required to balance transparency with security concerns effectively.

The appellant submitted that the Commissioner’s decision relied on evidence from the Home Office that was not disclosed to the appellant.

The appellant noted that the internal review was not sent on 16 May 2024.

The appellant submitted that the Commissioner failed to address systemic non-compliance with FOIA within the Home Office.

The Commissioner stated that he understood the scope of the request to be limited to information that was used to dispute the ICIBI’s findings, given the clear emphasis in the request on the Home Office’s response to the ICIBI report. He therefore considered that the information in the scope of the request was limited to the Home Office’s response to the report (referred to in the decision notice as document A) and the statistical data used in support (the GAIT dataset).

Of those two documents only the GAIT dataset remains in issue. The Commissioner’s response does not address the draft list of proposed redactions or the lists of factual inaccuracies.

The Commissioner submitted that it was often the case that the application of the prejudice test takes place where there is a risk of detrimental effect, rather than quantifiable damage. He said that the Tribunal held in Gilby v Information Commissioner & the Foreign and Commonwealth Office (EA/2007/0071) at [23], that a risk of this type was sufficient. He argued that ultimately there will be a degree of speculation required because the prejudicial event will not yet have occurred, although in order to demonstrate a causal link a public authority will need to provide some evidence as to how disclosure would lead to that prejudice.

The Commissioner stated that the Home Office provided detailed submissions including specific examples from the withheld information as to the prioritisation of resources which, if disclosed, would prejudice immigration controls by enabling individuals to undermine such measures.

He submitted that this, combined with the Commissioner’s review of the withheld information persuaded the Commissioner that the envisaged prejudice was of substance, there was a sufficient causal link and the chance of prejudice arising was more likely than not. The Commissioner submitted that when considering the withheld information, particularly the GAIT dataset and similar information, it was evident that disclosure would prejudice immigration controls and it was certainly more than a hypothetical or remote possibility.

In essence, the Commissioner maintained that the public interest favours withholding the requested information for the reasons given in the decision notice.

The Commissioner noted the information that was disclosed shortly after the request in the Home Office’s published response to the ICIBI’s report. He stated that this cast doubt on whether the relevant exemptions were engaged in respect of some of the information in the withheld documents and asked the Home Office to review and confirm its position in the light of the above.

The Commissioner submitted that it would be an error of law to consider any subsequent change in immigration controls as it would not shed light on the circumstances at the time of the request.

The Commissioner submitted that he was not required to consider further exemptions.

The Commissioner submitted that the time it took to complete an internal review was outside the scope of the tribunal’s jurisdiction.

The Commissioner submitted that this was outside the tribunal’s jurisdiction.

The appellant asserted that the GAIT dataset was likely to be potentially relevant, if it related to high-risk jet flights, but she submitted that it was not the full extent of the data within the scope of the request which was for evidence demonstrating compliance with security protocols including data, analysis and reports. She submitted that the Home Office’s response to the report (document A), the table of proposed redactions (document B) and the letter from Border Force (document D) were not in scope because they were unlikely to provide the operational or statistical evidence to demonstrate the proper security protocols were followed.

The appellant submitted that the GAIT dataset was historical statistical data and, if redacted, would not lead to the alleged harm. She submitted that a blanket approach had been taken and redactions not considered. She said that the alleged harm was speculative and unsupported. She argued that the Home Office have consistently failed to present concrete evidence demonstrating how this historical information could meaningfully compromise present or future immigration controls or the prevention of crime.

The appellant submitted that the public interest in disclosure was overwhelming, especially given the serious nature of the allegations made by David Neal regarding security lapses for high-risk private jet flights entering the UK, with far-reaching implications for public safety and trust in UK border security.

The Home Office agreed with and adopted the Commissioner’s response, save for the issue of what, if any, further information should be disclosed.

The Home Office agreed to the disclosure of the Home Office’s response to the ICIBI report (document A) as the finalised version was now in the public domain. The Home Office submitted in any event that document A was provided to the Commissioner as information and context and not as part of the withheld information.

The Home Office submitted that document B (the list of proposed redactions) and document C (the GAIT dataset) did not fall to be disclosed for the reasons given by the Commissioner in his decision notice and response.

The Home Office submitted that document D was not responsive to the request and was provided to the Commissioner as background. The Home Office agreed to the release of document D.

The appellant reiterated many of the previous arguments.

The appellant submitted that the disclosure of the Home Office’s response to the report (document A) undermines the credibility of the claimed exemptions and the Home Office’s position on the public interest balance in relation to the proposed redactions (document B) and the GAIT dataset (document C) and suggests that the harm is overstated.

The appellant submitted that the Home Office has failed to engage with the Commissioner’s recommendation to consider redaction. The appellant asserted that the Commissioner’s invitation to consider redactions was not limited to the Home Office’s response to the report (document A).

The Commissioner’s submissions, in essence were that he remained satisfied that section 31(1)(e) was engaged and that the public interest favoured maintaining the exemption. The Commissioner said that would also accept that section 24(1) FOIA was engaged, and the public interest favoured maintaining the exemption, for the reasons set out by the Home Office which were similar in concept to the reasoning for section 31(1)(e) FOIA.

The appellant’s submissions, in essence, were that the Home Office has still not identified with sufficient specificity how the contents of the request information would give rise to the claimed harms.

Section 31 FOIA provides a qualified exemption subject to the public interest test in respect of information relevant to specific areas of law enforcement:

The exemption is prejudice based. ‘Would or would be likely to’ means that the prejudice is more probable than not or that there is a real and significant risk of prejudice. The public authority must show that there is some causative link between the potential disclosure and the prejudice and that the prejudice is real, actual or of substance. The harm must relate to the interests protected by the exemption.

Section 24(1) provides, relevantly, that information is exempt if exemption is required for the purpose of national security.

Sections 24(1) and 31(1)(a) and (e) are qualified exemptions and subject to the public interest test. In APPGER v ICO and FCO [2013] UKUT 0560 (AAC) the Upper Tribunal gives helpful guidance on how the balancing exercise required by section 2(2)(b) of FOIA is carried out:

“… when assessing competing public interests under FOIA the correct approach is to identify the actual harm or prejudice that the proposed disclosure would (or would be likely to or may) cause and the actual benefits its disclosure would (or would be likely to or may) confer or promote. This … requires an appropriately detailed identification of, proof, explanation and examination of both (a) the harm or prejudice, and (b) benefits that the proposed disclosure of the relevant material in respect of which the exemption is claimed would (or would be likely to or may) cause or promote.” (para 75)

When multiple qualified exemptions apply, the public interest should be aggregated.

The Tribunal’s remit is governed by section 58 FOIA. This requires the Tribunal to consider whether the decision made by the Commissioner is in accordance with the law or, where the Commissioner’s decision involved exercising discretion, whether he should have exercised it differently. The Tribunal may receive evidence that was not before the Commissioner and may make different findings of fact from the Commissioner.

The issues for the tribunal to determine are:

We read an updated open and an updated closed bundle that had been updated following our case management orders.

The tribunal is satisfied that it is necessary to withhold the closed bundle from the appellant on the basis that to do otherwise would defeat the purpose of the appeal.

The open bundle includes a witness statement from Sonali Marcellina De Silva, from the National General Aviation Team in the Home Office.

The tribunal is not assisted by the decisions of previous first-tier tribunals or decision notices of the Commissioner that were cited by the parties.

Following the clarification, the Home Office’s position is that it held the following documents in scope at the time of the request:

The letter of 12 February 2024 has been disclosed and therefore our decision only concerns the first four documents. The first two documents had not previously been disclosed to the Commissioner or to the tribunal.

Taking into account the wording of the request we are satisfied that those documents fall within the scope of the request and that they were held at the date of the request.

The Home Office has not provided any substantive submissions in these proceedings on the exemptions. In its response to the appeal it adopted the Commissioner’s submissions. It did not provide any submissions, open or closed, following the case management orders of 26 January 2026.

The Home Office’s position therefore has to be gleaned from a number of different documents in the bundle including the response to the request, the Home Office’s submissions to the Commissioner, the Commissioner’s response to the appeal and the witness statement of Sonali de Silva. Most of those documents were drafted at a stage when the information/documents in scope of the request had not been clearly identified.

Although the Home Office was ordered to provide a witness statement addressing the specific content of the withheld documents, it has chosen not to produce a closed witness statement. That necessarily limits the specific reference that the witness can make to the content of the withheld information. The Home Office relies instead on a closed section of the submissions to the Commissioner. That section only addresses a small part of the withheld information. It was also drafted at a time when, for example, the factual inaccuracies documents had not been identified as being in scope. The open witness statement does not, in our view, provide a clear and detailed explanation of how the withheld documents, with reference to the specific content of those documents, would or would be likely to cause the asserted harm.

The following is our understanding of the Home Office’s position from the various documents in which it is set out.

In its response to the request and at internal review, the Home Office submitted that release of ‘sensitive security information’ could result in a mosaic effect enabling an individual to formulate a picture of how the Home Office consider security or national security checks for private jet flights and provide information that could be used to disrupt and prevent criminal and law enforcement activities. The Home Office said that the information could potentially provide enough information to enable criminals to target and disrupt security checks.

At that stage, the Home Office had not yet properly identified the information in scope at the relevant date and, of the documents in issue in the appeal, was only addressing the GAIT dataset (and other documents no longer in issue). The same applied when the Home Office made its submissions to the Commissioner.

In its submissions to the Commissioner, the Home Office submitted that disclosure of the information in the GAIT dataset would provide details about how Border Force risk-assess GA flights and allocate resources on a risk-based approach, including Home Office intelligence-related information. The Home Office submitted that if the risk based assessment framework were made public, individuals could seek to modify their actions based on knowledge of the framework to give them a greater chance of entering the UK unimpeded (for example, by seeking entry at locations where they believe coverage and scrutiny is likely to be minimal).

The Home Office submitted that it was essential that Border Force deploy their resources effectively and that the information that feeds into the risk assessment framework (which in turn leads to the deployment) is not disclosed. The Home Office submitted that making these ‘prioritisations’ known would pose a significant operational risk not only to the security of the border, but potentially to national security.

The closed submissions to the Commissioner refer to a number of specific factors/prioritisations and an example of specific staffing information. The Home Office explained, in open, that releasing this information could allow individuals to evade border security measures by adapting their behaviour by, for example, changing their nationalities when submitting their Advance Passenger Information to reduce the risk of being met. The submission stated that publicising information on staffing numbers, patterns and structures at airports would allow those seeking to illegally enter the UK to better understand the level of resource and assess the likelihood of being met by Border Force officials.

In relation to the public interest, the Home Office stated that:

“disclosure would have a detrimental effect on the security of the border: the release of sensitive immigration and security information held, specifically relating to the risk assessment and staffing levels could result in a mosaic effect enabling individuals to formulate a picture of how the Home Office consider immigration and security checks for private jets, in order to disrupt and prevent immigration, criminal and law enforcement activities. Releasing the information could enable those who engage in active criminality, and worse (e.g., those who pose a national security risks), with sufficient information to enable them to target and disrupt security checks which are conducted for private jet flights into the UK. It is considered that this is a weighty factor in the public interest assessment.”

Specifically in relation to national security, the Home Office said in its submissions to the Commissioner that the GAIT dataset could potentially provide enough information to enable an individual to build up a bigger picture of how Border Force consider immigration and security checks:

“It could therefore allow someone to target operations not only at London City Airport, but also to use the details for risk classification, to seek to avoid or circumvent immigration control nationally - the mosaic effect. Further, it would allow those who pose a national security risk to evade scrutiny more easily on arrival.”

The arguments in the Commissioner’s response, which were adopted by the Home Office, are set out above and reflect the arguments in the Home Office submissions to the Commissioner.

The witness statement of Sonali Marcellina De Silva is the only place in which the Home Office address the lists of factual inaccuracies (draft and final) and the draft proposed list redactions. Ms De Silva states as follows:

“This is an OPEN witness statement which therefore limits how much I am able to say about the reasons for applying the exemptions in this case. I rely on the full, unredacted submission to the Commissioner (dated 16 August 2024) [CB140-149] which includes CLOSED submissions for applying the exemptions and therefore I have not submitted a separate CLOSED statement.” [29]

Although she relies on closed submissions to the Commissioner, those submissions are, as noted, limited and do not address the lists of factual inaccuracies or the draft proposed list of redactions.

Ms De Silva describes her role as follows:

“I work within the National General Aviation ("GA") Team in Border Force UK Command Operations (UKCO), which has responsibility for the strategic coordination, oversight and assurance of GA activity at the UK border. My role involves informing and influencing national work to identify and mitigate vulnerabilities arising from private flights covering leisure and business aviation, in collaboration with regional commands, intelligence partners, policy colleagues and cross government partners. All to support the governance and assurance of GA processes to enable effective and proportionate operational decision-making.”

We accept that Ms De Silva is well placed to assess the likelihood of harm, in particular, to the operation of immigration controls. Her witness statement does not state that she has particular expertise in relation to national security or the prevention and detection of crime although she works in collaboration with partners, including intelligence partners, in informing and influencing national work on identifying and mitigating vulnerabilities arising from private flights.

Despite her expertise, for the following reasons the weight we placed on her witness statement was reduced.

First, Ms De Silva relied on earlier closed submissions that had been drafted before three of the documents in issue before the tribunal had been identified. The extent to which those earlier submissions referred to specific content of the withheld information was, in any event, limited.

Second, the witness statement focussed primarily on the GAIT dataset, and the evidence she gave in relation to the draft list of proposed redactions and the lists of factual inaccuracies was limited. She gave no specific evidence on the impact of disclosure of the ‘headline statistics’. Her evidence, did not, in the main, include a clear and detailed explanation of the likely harm with specific reference to the content of the withheld information. This was, in part, because the Home Office chose not to produce a closed witness statement.

Third, much of the content of the proposed draft list of redactions, which was drafted by Ms De Silva and which she asserted was exempt in its entirety under sections 31(1)(a), 31(1)(e) and 24, did not appear in the proposed final list of redactions and was made public in the ICIBI report on 26 March 2024 approximately one week after the response to the request. Indeed, much of it provides no more detail than is provided in the witness statement itself.

Although the tribunal ordered that the Home Office address the issue of whether redactions could be made to reduce or remove the risk of harm, this was not done in relation to the proposed list of redactions.

Ms De Silva’s blanket approach to the proposed final list of documents, and her evidence that disclosure of any of the information in the document would lead to the suggested harm, which was clearly unsupportable given the content of that document, led the Tribunal to approach the rest of her evidence with some caution.

In relation to prejudice to the operation of immigration controls under section 31(1)e), Ms De Silva stated that disclosure would expose Border Force’s risk assessment methods, intelligence-linked criteria and operational deployment patterns, which would enable bad actors to exploit gaps in the system which would undermine the operation of immigration controls.

In relation to the GAIT dataset, Ms De Silva said that the dataset was essentially a risk assessment framework. She said that it included the number of flight arrivals, the GARAT assessment rating, the reasoning as to whether the flight was classified as high-risk, the Border Force operational response to the flight and whether it was physically met or cleared remotely. It also recorded comments on the nationalities of certain individuals arriving on the flight to support the rationale for the flight's classification, both pre - and post-review.

Ms De Silva explained that disclosure of the information in the GAIT dataset would provide details about how Border Force risk assesses GA flights and allocates resources according to a risk-based approach. She said that the operation of immigration controls would be prejudiced because disclosure could allow individuals seeking to evade immigration controls to modify their actions, given knowledge of the risk assessment framework, for example by seeking entry at locations where they believe coverage and scrutiny is likely to be minimal or declaring a different nationality when submitting their GAR. She said that this applied to criminal or terrorist actors. She said that making Border Force’s “prioritisations” known would pose a significant operational risk to both border security and, potentially, national security.

In relation to the proposed redactions to the ICIBI report, she submitted that they reveal information about Border Force’s process of risk assessment and security operations with the same anticipated effects as release of the GAIT dataset. She relied in addition on the ‘rationale’ column in the final version of the proposed redactions and the ‘suggested amendment/redaction’ column in the draft version of the proposed redactions to justify engaging the exemption. We deal with this in our closed reasoning.

In relation to the list of factual inaccuracies (draft and final) Ms De Silva said that they include information on security operations which was redacted from the final published version of the report. She listed the rows in which this information appeared and said that this information therefore engaged the exemption under section 24 and section 31. She accepted that the remainder of the document was disclosable.

In relation to the public interest in maintaining section 31(1)(e), Ms De Silva said that the release of sensitive immigration and security information held, specifically relating to the risk assessment and staffing levels could result in a mosaic effect enabling individuals to formulate a picture of how the Home Office consider immigration and security checks for private flights, in order to disrupt and prevent immigration, criminal and law enforcement activities. She said that releasing the information could enable those who engage in active criminality, and worse (e.g., those who pose a national security risks), with sufficient information to enable them to target and disrupt security checks which are conducted for private flights into the UK.

In relation to section 31(1)(a) (prevention or detection of crime), Ms De Silva explained that release of the information would allow criminals to infer law enforcement activity, adapt their behaviour to minimise scrutiny and undermine joint operational activity with policing and intelligence partners. She explained that immigration officials work closely with other enforcement partners and information is securely shared between them.

Ms De Silva said that if sensitive statistical information, and data related to internal processes at the ports were to be disclosed, it could compromise any on-going or future law enforcement operations, thereby undermining the important work in upholding law and order and keeping the public safe from crime. She said that for similar reasons already provided under section 31(1)(e), disclosure could be used by criminals with malicious intent to infer how our security controls/protocols work, and therefore they could adapt their approach and behaviours to minimise scrutiny and/or avoid border checks to gain entry to the UK, thereby posing a real risk to the public from criminality. She said that disclosure would prejudice the ability of law enforcement partners to prevent or detect crime not just at LCY, but because of the inferences which could be made, to other ports across the UK too, because of the mosaic effect.

In relation to the public interest she said that any release of sensitive security information, specifically regarding the disclosure of immigration checkpoints information, could result in a mosaic effect enabling an individual to formulate a picture of how the Home Office consider security checks for GA arrivals to disrupt and prevent criminal and law enforcement activities.

In relation to section 24, Ms De Silva said that the reasons for relying on section 24 were similar to those for the two other exemptions. She said that disclosure would give hostile actors, including terrorists or state-based threats, insight into security screening methods and vulnerabilities, enabling them to circumvent border controls and increasing risks to national security. She said that this was why exemption was required for the purpose of safeguarding national security.

Ms De Silva said, at paragraph 47, that this was ‘particularly true’ of the record of GA arrivals at LCY in 2023 [CB12-102], the proposed redactions to the draft ICIBI report [CB103-112 and CB163-172] and the information within the factual accuracy document (both draft [CB150-152] and final [CB153-162]) which was ultimately redacted from the final published ICIBI report. The tribunal notes that this list of documents in relation to which Ms De Silva said this was ‘particularly true’ includes the entirety of the withheld information plus one document which was not held at the time and is therefore outside the scope of the request.

Ms De Silva said that information contained in ‘these documents’ (i.e. all the withheld information) could potentially provide enough information to enable an individual to build up a bigger picture of how Border Force consider immigration and security checks. It could therefore allow someone to target operations not only at London City Airport, but also to use the details for risk classification, to seek to avoid or circumvent immigration controls nationally - the mosaic effect. Further, she said that it would allow those who pose a national security risk to evade scrutiny more easily on arrival. Such individuals entering the UK pose a significant risk to national security.

Ms De Silva said that if sensitive statistical information and data related to internal processes at the ports were to be disclosed, it could compromise any on-going or future law enforcement operations, undermining the important work in keeping the public safe and safeguarding the UK.

Further detail on the Home Office’s arguments on section 24, that it said applied also to the GAIT dataset are set out below.

In relation to the public interest under section 24, she said that disclosure would result in a real risk to national security.

The asserted prejudice, that bad actors would modify their actions to increase their chance of evading border control, relates to the interests protected by the exemption and is real, actual and of substance.

Despite our reservations about Ms De Silva’s evidence, we are persuaded by her evidence on the risks of disclosure of the entirety GAIT dataset. We have reviewed the GAIT dataset in the closed bundle. It contains detailed information about every GA flight arrival at LCY in 2023, including details of the specific aircraft, the departure and arrival port, the arrival date and time, the risk classification, whether or not each aircraft was met, whether each identified flight was categorised as high risk and an explanation of why that decision was reached. In some cases, the explanation of why the decision was reached includes reference to intelligence information and in most cases it reveals the criteria that is applied.

The dataset is recent: it applies to arrivals at LCY in 2023, which, at the relevant time, was the most recent calendar year. The dataset contains multiple categories of data for each identifiable flight. Although LCY only receives 1.8% of GA arrivals in the UK, that amounts to 1407 GA arrivals in 2023. That combination enables valuable inferences to be made about the criteria that is applied nationally. The dataset gives a complete picture, in a recent period, of how those criteria were applied and resources allocated at LCY. That gives valuable information about how that criteria were likely to be applied at LCY at the relevant date.

Even without any informed analysis of the dataset, it was possible for the tribunal to discern detailed information about how Border Force risk assesses flights and allocates resources according to a risk-based approach. That is possible on a first reading of the information because it includes narrative of the reasons for the risk classification and of the reasons why the aircraft was or was not met.

We accept Ms De Silva’s evidence that disclosing this dataset would reveal the Border Force’s ‘prioritisations’ and that there is a causative link between disclosure and a real and significant risk of bad actors modifying their actions to increase their chance of evading immigration controls.

Having considered the GAIT dataset we are not persuaded that it is possible to avoid harm by making redactions of certain information. The prejudice arises out of disclosure of ‘the dataset’ rather than from disclosure of specific rows or specific columns.

We find that section 31(1)(e) is engaged in relation to the entirety of the GAIT dataset.

We also accept that section 24 is engaged in relation to the GAIT dataset, fundamentally for the same underlying reason given in relation to section 31(1)(e).

Ms De Silva dealt with section 24 in paragraphs 46 to 49. She relies primarily on the reasoning set out earlier in her witness statement under sections 31(1)(a) and (e). Paragraphs 46-49 do not distinguish between the different withheld documents or between the different information in those documents. Ms De Silva stated in paragraph 46 that:

“The requested information also helps play a critical part in protecting the public more generally against wider threats, such as those associated with terrorism. Disclosure would give hostile actors, including terrorists or state based threats, insight into security screening methods and vulnerabilities, enabling them to circumvent border controls and increasing risks to national security. It is for this reason that the withheld information is required for the purpose of national security.”

In paragraph 47, as highlighted above, Ms De Silva asserted that this was ‘particularly true’ of all the withheld information. She said that:

“Information contained within these documents could potentially provide enough information to enable an individual to build up a bigger picture of how Border Force consider immigration and security checks. It could therefore allow someone to target operations not only at London City Airport, but also to use the details for risk classification, to seek to avoid or circumvent immigration controls nationally - the mosaic effect. Further, it would allow those who pose a national security risk to evade scrutiny more easily on arrival.”

Given the content of the draft proposed redactions document, as discussed below, we believe that the statement that this is ‘particularly true’ of all the documents is significantly overstated, and that has led us to approach Ms De Silva’s assertions with some scepticism. In particular we note that much of the information that Ms De Silva proposed should be redacted was not redacted from the report, and was made public on 27 March 2024, presumably on the basis that publication was not thought by the Secretary of State to be undesirable for reasons of national security (see the discussion of section 50 of the UK Borders Act 2007 below).

However, in relation to the GAIT dataset, we accept the section 24 arguments set out above and those we detail below. We accept that the detailed information in the GAIT dataset that is valuable to bad actors seeking to evade immigration controls would also be valuable to terrorists seeking to evade detection on entry. On that basis we are satisfied that withholding the GAIT dataset is reasonably necessary to safeguard national security.

It was not necessary for us to reach a conclusion on section 31(1)(a) in relation to the GAIT dataset.

We accept that sections 31(1)(e) and section 24 are engaged in relation to information in the factual inaccuracies documents or in the draft redactions document that reveals the criteria that Border Force apply in terms of risk classification or the criteria that is applied to decide whether or not a flight is met. We repeat and rely on our reasoning above for that conclusion. A list of the information that falls within this category is set out in the closed annex. We refer to this information as ‘Criteria related information’

We accept that that publicising information on Border Force staffing levels at particular airports would allow those seeking to illegally enter the UK to better understand the level of resource available. We accept Ms De Silva’s evidence and the Home Office submissions that there is a causative link between disclosure of this information and a real and significant risk of bad actors modifying their actions to increase their chance of evading immigration controls. We rely in addition on our reasons above. We also accept that section 24 is engaged in relation to this information for the same reasons as the section 31(1)(e).

We accept that section 31(1)(e) and section 24 are engaged in relation to any of this information that appears in the factual inaccuracies documents and the draft proposed redactions. This information is identified in the closed annex and is referred to as ‘Staffing information’.

In summary, it was not evident to the tribunal how disclosure of this information would or would be likely to cause the relevant prejudice or why exemption was required for the purpose of safeguarding national security. Despite the tribunal’s orders, the Home Office has not provided an explanation, with reference to these specific categories of information, why disclosure would or would be likely to cause the asserted harm or why exemption is required for national security. Without that explanation, because the mechanism that would lead to prejudice/the need for exemption is not evident to us, we are unable to find that the exemption is engaged on the basis of an assertion by the Home Office. Without that explanation we would be unable to explain, in our reasons, why we had reached the conclusion that the exemption was engaged in relation to the headline statistics and GA guidance figures.

The final factual inaccuracies document and the draft proposed redactions include headline figures on:

We refer to those figures as ‘headline statistics’.

Those documents also include figures for the number of cases in the random sample of cases used by the ICIBI inspectorsthe number of cases in the sample that had been rated as high risk because passengers had not been checked against Home Office intelligence and other systems.

We refer to those figures as ‘other figures’.

The headline statistics and other figures are based on the GAIT dataset, but do not reveal any of the detailed information which is included in the GAIT dataset. They do not reveal any information about any particular GA flight arrival at LCY. They do not reveal any details of the specific aircraft, the departure and arrival port, the arrival date and time, the risk classification of any particular flight, whether or not a particular aircraft was met, or whether any identified flight was categorised as high risk. They do not reveal any of the reasoning for the classification. They do not reveal or refer to intelligence information and do not reveal criteria or provide any information from which criteria can be inferred.

Those figures were redacted from the published ICIBI report. In relation to the headline statistics the factual inaccuracies document includes the figures that the ICIBI proposed to include in the report and the alternative figures that the Home Office contended were accurate.

We are not persuaded on the basis of the evidence before us that the second respondent has established a causative link between the claimed prejudice under section 31(1)(a) and 31(1)(e) and disclosure of the headline statistics or other figures.

The Home Office has not adequately explained how knowledge of the number of flights that were categorised as high or low risk at LCY in 2023 or how knowledge of the percentage of those that were met at LCY would or would be likely to cause prejudice to immigration controls or the prevention or detection of crime, whether on its own or as a contribution to the ‘mosaic effect’ combined with other information that bad actors might have access to. In the absence of such an explanation, we do not know how knowledge of these headline statistics could enable bad actors to take steps to evade border control.

The Home Office’s submissions on disclosure, whether of the information itself, or as a contribution to ‘the mosaic effect’ combined with other information, focus on information that discloses information about the risk assessment framework and on information on staffing levels.

The Home Office was ordered, in the witness statement, to give a clear and detailed explanation of how the withheld documents, with reference to the specific contents of those documents, would or would be likely to cause the asserted harm, with reference any of sections 31(1)(a), (e) and 24(1) FOIA on which the Home Office continues to rely.

Ms De Silva addressed the draft proposed redaction document in paragraph 22 of her witness statement. She said that the document reveals information about the Border Force’s process of risk assessment and security operations. She said that this information had the same anticipated effects as described above. We have accepted that section 31(1)(e) is engaged in relation to information that reveals the criteria and staffing levels, but Ms De Silva does not explain how, without the detailed information contained in the GAIT dataset, the headline statistics or other figures reveal information about the process of risk assessment or security operations nor does she explain how that information could be used by bad actors to cause prejudice to border operations.

Ms De Silva relied in addition on the “rationale” column in the final version of the proposed redactions and the “suggested amendment/redaction” column in the draft version to justify engagement of the exemption. Although the final version is not in scope, we have considered the relevant columns in both documents. As explained in the closed annex, nothing in those columns explains how the headline statistics or other figures could be used by bad actors to cause the relevant prejudice. The “rationale column” simply contains an assertion of prejudice with no explanation and the “suggested amendment/redaction” contains no justification or explanation for redaction of the headline statistics or other figures.

The headline statistics and other figures also appear in the factual inaccuracies documents. Ms De Silva’s evidence in paragraph 24 of her witness statements was that this information was redacted from the final published version of the ICIBI’s report on grounds of national security and therefore this information engages the exemption under section 24 and “as I explain further below” exemptions under section 31 as well. There is no explanation in this paragraph of why exemption is required for the purpose of national security. We deal with section 24 below. As stated above Ms De Silva does not explain clearly at any point in the witness statement why the release of headline statistics or other figures would or would be likely to lead to the relevant harm.

In relation to Ms De Silva’s evidence on section 31(1)(a), it is not always clear when she is giving evidence in relation to the GAIT dataset and when she is giving evidence in relation to the information in the draft proposed redactions document or the factual inaccuracies documents.

Ms De Silva said in paragraph 40 of her witness statement that if “sensitive statistical information” were to be disclosed, it could compromise any on-going or future law enforcement operations, thereby undermining the important work in upholding law and order and keeping the public safe from crime.

She said that for similar reasons already provided under section 31(1)(e), disclosure could be used by criminals with malicious intent to infer how our security controls/protocols work, and therefore they could adapt their approach and behaviours to minimise scrutiny and/or avoid border checks to gain entry to the UK, thereby posing a real risk to the public from criminality. She said that disclosure would prejudice the ability of law enforcement partners to prevent or detect crime not just at LCY, but because of the inferences which could be made, to other ports across the UK too, because of the mosaic effect.

When Ms De Silva talks about ‘sensitive statistical information’, we take this to be a reference to the GAIT dataset, not to information in the draft proposed redactions document or the factual inaccuracies documents. We reach this conclusion because this exact phrase was used in the submission to the Commissioner, which was drafted at a time when these documents had not been identified as being in scope of the request, and which refer explicitly to document C (the GAIT dataset):

“Due to the nature of their work, immigration officials work closely with other law enforcement partners, and information is securely shared between them, e.g. information sourced from Doc C. If sensitive statistical information, and data related to internal processes at the ports were to be disclosed, it could compromise any on-going or future law enforcement operations, thereby undermining the important work in upholding law and order and keeping the public safe from crime.

For similar reasons already provided under section 31(1)(e), disclosure of the requested information could be used by criminals with malicious intent to infer how our security controls/protocols work, and therefore they could adapt their approach and behaviours to minimise scrutiny and/or avoid border checks to gain entry to the UK, thereby posing a real risk to the public from criminality.”

In support of this, we note that the Commissioner, in his response which was adopted by the Home Office, refers to the GAIT dataset as “statistical data of manual records for London City Airport for the period 1 January – 31 December 2023”.

Even if we are wrong, and the reference to ‘statistical information’ in paragraph is a reference to the headline statistics or other figures redacted from the final report, we are not satisfied that there is a clear explanation in that paragraph of how the headline statistics or other figures could be used. Ms De Silva does not explain how the headline statistics or other figures could be used to ‘infer how security controls/protocols work’ nor does she explain how behaviour could be adapted in the light of the headline statistics or other figures to minimise scrutiny and/or avoid border checks.

In the absence of any clear explanation of the link between disclosure of the headline statistics and the claimed harm, we are not satisfied that there is a causative link between disclosure of the headline statistics or other figures and the asserted prejudice under section 31(1)(a) or (e). The Home Office has not discharged the evidential burden of showing that some causal relationship exists between the potential disclosure and the claimed prejudice. On that basis we find that sections 31(1)(a) and (e) are not engaged in relation to the headline statistics.

In relation to section 24, Ms De Silva asserted at paragraph 22 of her witness statement that this information is exempt under section 24 because it was redacted from the report on grounds of national security. She provides no explanation in that paragraph of why withholding the information is required for the purpose of national security. We note that the Home Office’s response to the report states that “All redactions of material from the inspection report, are for reasons of national security and have been made by the Home Secretary in accordance with the UK Borders Act 2007”. There is no explanation for the reasoning behind that decision. As stated above, the “rationale” column in the final proposed redactions document simply asserts prejudice without explaining how the headline statistics or other figures could be used, and there is no additional rationale in the factual inaccuracies documents.

We have accepted the evidence in paragraph 47 of the witness statement in relation to the harm that would be likely to be caused by disclosure of the detailed information contained in the GAIT dataset, for the reasons set out above, because the mechanism has been clearly explained.

In contrast, it is not clear to the tribunal, and Ms De Silva has not explained, how disclosure of the headline statistics or other figures would give insight into security screening methods or vulnerabilities and it is not clear to us how disclosure of the headline statistics or other figures would enable hostile actors or terrorists or state-based threats to circumvent border controls. It has not been explained to us how the headline statistics or other figures, whether alone or as part of a mosaic of information, could allow someone to target operations at LCY or to seek to avoid or circumvent immigration controls nationally, or to evade scrutiny more easily on arrival.

It was not drawn to our attention by the Home Office, in submissions or in the witness statement, but we note that the ICIBI report published on 26 March 2024 states as follows:

“Reports are published in full except for any material that the Secretary of State determines it is undesirable to publish for reasons of national security, in which case the legislation permits the Secretary of State to omit the relevant passages from the published report.”

We note that there is a similar statement in the Home Office response, also published on 26 March 2024, also not drawn to our attention by the Home Office, which states:

“All redactions of material from the inspection report, are for reasons of national security and have been made by the Home Secretary in accordance with the UK Borders Act 2007.”

The relevant provision is section 50(3)(a) of the UK Borders Act 2007 which provides that the copy of the Chief Inspector’s report laid before Parliament may omit material if the Secretary of State thinks that its publication is undesirable for reasons of national security.

The test that we have to apply under section 24 is different to that under section 50(3)(a) of the UK Borders Act. We note that the Secretary of State’s view was that publication of this information was ‘undesirable for reasons of national security’, but that does not automatically satisfy section 24. The tribunal must be satisfied that exemption from section 1(1)(b) is required for the purpose of safeguarding national security in the sense that withholding the information is reasonably necessary on the basis that disclosure would give rise to the real possibility of direct or indirect damage being done to national security or, put another way, that exemption is reasonably necessary to prevent a real and substantial increase in the risk of attack on national security.

There is no evidence before us of the basis of the Secretary of State’s view that disclosure was undesirable. There is provision under section 24(3) for the public authority to produce a certificate signed by a Minister to the effect that exemption is required for the purpose of safeguarding national security, which would be conclusive evidence of the fact, but no such certificate has been produced. We are conscious of the need to attach due weight to the executive’s assessment of what is required for the purpose of safeguarding national security, but where no certificate is produced, an adequate explanation of the rationale for that assessment must be provided. In relation to the headline statistics or other figures we are not satisfied such an explanation has been provided. On that basis we find that section 24 is not engaged in relation to the headline statistics or other figures.

An additional piece of information that appears in the withheld documents was the proportion of high-risk flights that are required to be met by Home Office GA guidance and the percentage of low-risk flights that the guidance said should be met. We refer to this information as ‘the proportions from the GA guidance’. The first piece of information appears, unredacted, in the ICIBI report that was published 7 days after the response to the request. The percentage of low-risk flights that should be met was redacted from the published ICIBI report, for example:

“Home Office GA guidance requires all high-risk flights to be physically met, and states that at least [redacted] [of low-risk flights should be physically met for assurance purposes” [1.4]

However although the percentage figure that appears in the guidance is redacted from the published report, the introduction states as follows:

“Guidance designed to keep the country safe directs that all GA flights identified as high risk are met by Border Force staff, except in exceptional circumstances. … Guidance also directs that a third of low-risk flights are met.”

As further explained in closed, we are not persuaded that there is a rationale distinction between the redacted percentage and the published fraction of low-risk flights that the GA Guidance says should be met, in terms of the potential harm that might follow from disclosure.

Whilst the ICIBI report was not published at the time of the response to the request, it was published 7 days later. The submissions from the Home Office, as contained in various documents outlined above, do not provide any explanation for why publication of the proportion of high-risk and low-risk flights that should be met would be likely to cause the suggested harm or that withholding that figure is required for the purpose of national security, particularly in the light of the publication of those proportions in the ICIBI report.

On that basis we find that none of the exemptions are engaged in relation to the proportions from the GA guidance.

We have reached these conclusions with caution given the decision of the Secretary of State to redact the headline statistics and the GA guidance percentage figure from the published ICIBI report.

Although a different test applies under the UK Borders Act 2007, the tribunal is conscious of the Secretary of State’s relevant institutional expertise and the need to give due weight on the views of those who are particularly well placed to judge the risks of disclosure, particularly in relation to national security.

Further we accept that, in principle, high level statistics can contribute to a ‘mosaic’ of information that might assist bad actors. However, not all high-level statistics will do so, and it has not been explained how that could happen in relation to the ones under consideration. We are not in a position to make our own operational assessment of how these particular figures would be likely to cause the relevant harm or why it is reasonably necessary to withhold them for purpose of safeguarding national security.

On the basis of the information before us, we are not satisfied that the exemptions are engaged.

The Home Office’s position, and Ms De Silva’s evidence, is that the entirety of the draft proposed redactions document should be withheld because disclosure would be likely to give bad actors the opportunity to evade or circumvent security checks. That is their position even though the vast majority of the draft proposed redactions were not included in the final proposed redactions document and that those redactions were not made to the final ICIBI report when it was published 7 days after the Home Office’s response to the request. Much of that information also appears in the Home Office’s witness statement.

The submissions from the Home Office, as contained in various documents outlined above, do not provide any explanation for why the remainder of the information would be likely to cause the suggested harm, particularly in the light of its inclusion in the ICIBI report and the witness statement.

On that basis we are not persuaded that the Home Office has shown that the relevant prejudice under section 31(1)(a) or (e) would be likely to be caused by disclosure, nor are we persuaded that withholding the information is required for the purpose of safeguarding national security. That information is referred to in the decision notice above and in the closed annex as ‘the remainder of the information in the draft proposed redactions document’. We find that the exemptions are not engaged in relation to that information.

We are not persuaded that anything else in the rows in the factual inaccuracies documents that specified in the witness statement could lead to the asserted harm. Some of it is reproduced in the published report. Some of it is, as far as we can tell, entirely innocuous information and the witness statement and the submissions from the Home Office, as contained in various documents outlined above, do not provide any explanation for why the remainder of the information would be likely to cause the suggested harm, or why withholding the information is required to safeguard national security. We find that the exemptions are not engaged in relation to that information.

We have found that section 31(1)(e) and section 24 are engaged in relation to:

It is appropriate to aggregate the public interest in withholding the information under each of the exemptions, although we would have reached the same conclusion in relation to each exemption considered separately.

Taken together, we find that there is a very weighty public interest in maintaining the exemptions. Where exemption is required for the purpose of national security, there is a very strong public interest in maintaining the exemption. Whilst the risk of terrorism is low, its potential impact is extremely severe, and therefore even a small increase in the risk of terrorism carries significant weight in the public interest balance. We find that there is also a very strong public interest in avoiding prejudice to the operation of immigration controls and in avoiding prejudice to the prevention or detection of crime. We accept that protecting the UK border is of paramount importance to the Government and that securing the border plays a critical role in protecting the public from crime.

Weighed against this, we accept that the GAIT dataset would allow the public to scrutinise the raw data underlying the conclusions reached in the ICIBI report. The public would be able to scrutinise the raw data showing the reasons for the risk classification of each flight the detail of why each flight was or was not physically met on arrival.

The Home Office said in its response to the request and in the letter of 12 February 2024 that the GAIT dataset supported the Home Office’s assertion that LCY has been assessing and recording GA flights in a manner that differs from the rest of Border Force and is contrary to standard practice, or how it shows that a large proportion of flights recorded as high-risk should have been reclassified as low-risk. Disclosure of the GAIT dataset would allow the public to interrogate whether the GAIT dataset supported that assertion.

That would contribute to informed debate, particularly in relation to the serious issues raised in the ICIBI report. We accept that there is a heightened public interest in transparency as a result of the issues raised in that report. We find that there is a strong public interest in disclosure of the GAIT data.

Although Ofqual V Information Commissioner [2023] UKUT 253 (AAC) means that we cannot take account in the public interest balance of the imminent publication of the report and the Home Office response, we can take account of information that would have been disclosed in response to the request because it was not exempt.

Disclosure of the headline statistics, the GA guidance figures and the rationale in the factual inaccuracies documents for disputing some of those statistics, would have contributed to some extent to informed public debate on this issue. That would have been disclosed in response to the request and accordingly reduces the public interest in disclosure of the underlying raw data to some extent.

In relation to the Criteria related information and Staffing information, whilst there is a general public interest in transparency and in understanding the way in which Border Force operates, this information does not serve the particular public interest which the appellant has identified, i.e. it would not materially contribute to informed debate in relation to the issues raised by the ICIBI report.

For all the information in relation to which we have found the exemptions engaged we find that the public interest in maintaining the exemptions outweighs the public interest in disclosure. The public interest in disclosure of the GAIT dataset is strong, but it is outweighed by the very strong public interest in maintaining the exemptions, whether aggregated or taken individually.

Although we have held that the public interest in disclosure of the GAIT statistics is reduced to some extent by disclosure of the information that we have held is not exempt, without this reduction we would have found that the public interest favoured maintaining the exemptions in any event, because of the very strong public interest in avoiding the harms protected by the exemptions in issue.

Our decision above deals with grounds 1-3 (as identified by the tribunal). We deal briefly with the remaining grounds here.

In relation to ground 4, there is no requirement for the Commissioner, or the tribunal, to make findings on all exemptions. Where one exemption is sufficient to dispose of the matter, only that exemption needs to be ruled on.

In relation to ground 5, we stand in the shoes of the Commissioner, and any procedural unfairness can be cured by our full merits review. We are satisfied that it is necessary to withhold the closed information from the appellant.

In relation to ground 6 there is no requirement in FOIA to conduct an internal review and a failure to conduct an internal review is not a matter that can form the basis of a section 50 complaint to the Commissioner or an appeal to the tribunal.

In relation to ground 7, the Commissioner’s role is to determine whether, in any specified respect, a request for information made by the complainant to a public authority has been dealt with in accordance with the requirements of Part I FOIA. The tribunal’s role is to consider whether the decision made by the Commissioner is in accordance with the law or, where the Commissioner’s decision involved exercising discretion, whether he should have exercised it differently. It is not part of the Commissioner’s role on a section 50 complaint nor part of the tribunal’s role on appeal to address systemic non-compliance with FOIA.

The following information is exempt under section 31(1)(e) and section 24:

The exemptions are not engaged in relation to the rest of the withheld information, i.e. the Headline statistics; the GA guidance figures and the remainder of the information in the factual inaccuracies documents and the draft proposed redactions.

The specific parts of the withheld information that fall into each of these categories are identified in a closed annex.