R v Tristram Dillon

On 6 October 2025, the appellant pleaded guilty at the magistrates' court to inflicting grievous bodily harm on Mr Kaz Theuri, contrary to section 20 of the Offences against the Person Act 1861. He was committed to the Crown Court for sentence.

On 10 February 2026, in the Crown Court at Southwark, he was sentenced to 22 months' imprisonment by His Honour Judge Hiddleston.

The appellant now appeals against that sentence with the leave of the single judge.

At the time of the offence the appellant and Mr Theuri were working as security officers at the University of Westminster.

On 17 March 2024, Mr Theuri returned from a designated break at approximately midday. There was a difference of opinion about whether Mr Theuri had updated the security system. The appellant stood up from his desk and walked over to Mr Theuri, who also stood up as the appellant approached him. The appellant then stood directly in front of Mr Theuri and repeatedly said the word "What?" Mr Theuri told the appellant that he was not afraid of him. The appellant then struck Mr Theuri on the left side of his face. Mr Theuri attempted to take hold of the appellant to defend himself, but the appellant grabbed hold of Mr Theuri's face, and struck him to the body and then again to the head. The appellant then dragged Mr Theuri to the ground. Once he was on the ground, the appellant repeatedly punched Mr Theuri to the face to such an extent that Mr Theuri saw his own blood around him on the floor. Mr Theuri attempted to stand up, but the appellant used both hands to push him back down to the ground and stood over him for a short time. The appellant then left the desk area before returning to mock Mr Theuri for the appearance of his face after the appellant had punched him.

The police attended and took an account from both Mr Theuri and the appellant. The appellant made admissions at the scene to throwing the first punch and multiple punches thereafter.

Mr Theuri sustained a broken right ankle and a broken nose and was taken to hospital.

At the sentencing hearing it was common ground that the offence fell within medium culpability: B on the Sentencing Guideline for section 20 offences. There was a dispute however, about whether the harm caused to Mr Theuri fell within category 1 on the basis that he had sustained permanent, irreversible, injury which had a substantial and long term effect on his ability to carry out his normal day to day activities or on his ability to work, as the prosecution contended.

In connection with the issue of categorisation, the judge was provided with a victim personal statement, dated 13 January 2026 (nearly two years after the incident), which Mr Theuri read to the court. This gave an account of the effect of his injuries and the treatment which he had received. In summary, in relation to the ankle injury he stated that he continued not to be able to walk properly and had pain and discomfort above the ankle when he did so. He worried that he would always have a limp. Before the incident he had been exercising to lower his raised cholesterol levels, and his loss of mobility meant that they remained raised. He had had to move back in with his parents for a year. His hobbies, his self-esteem and his social life were also affected. His mood had changed and he was now self-conscious. A depressed area on his head was a constant reminder to him of what had happened.

The judge also had medical evidence in the form of an SFR/13 detailing the injuries sustained by Mr Theuri, the assessment at the hospital on 17 March 2024, and a series of updates, up to and including an assessment on 18 June 2024.

There was also a report from a Dr Michael Kim, dated 22 January 2026. Dr Kim stated that Mr Theuri had sustained a comminuted fracture of the distal fibula – i.e. the ankle bone was broken into multiple pieces. This was a serious ankle injury, said Dr Kim, which required immobilisation in a plaster cast, a prolonged period of not putting weight on it, and ongoing orthopaedic follow up. By June 2024 the fracture was documented as healing, and Mr Theuri was able to walk without a protective boot. However, there was evidence of loss of muscle bulk in the right calf, which was consistent with prolonged immobilisation and reduced use of the limb. As for the prognosis in relation to the ankle injury, Dr Kim stated that although the bone had healed, ankle fractures of this nature carry a risk of long term complications, which may include ongoing stiffness, weakness, pain on prolonged standing or walking, and reduced tolerance for high impact activity. Whilst physiotherapy might improve strength and function, full restoration to pre-injury levels could not, in Dr Kim's view, be guaranteed. There was also, said Dr Kim, a recognised risk of early wear and tear in the ankle joint over time. He went on to say:

Dr Kim stated that the broken nose was treated with manipulation shortly after the injury. Whilst this improved the external appearance of the nose, the assessment of the Ear, Nose and Throat specialist one year later documented a significant deviation of the nasal septum. This was associated with ongoing nasal obstruction and snoring, which indicated a persistent, functional problem, rather than a purely cosmetic issue. Septoplasty under general anaesthetic had been discussed as a potential treatment, but while such surgery carries a likelihood of improving nasal airflow, it does not guarantee complete resolution of symptoms and carries recognised risks. Dr Kim said that in the absence of surgery, ongoing nasal congestion and related symptoms may persist.

There was also a psychological report prepared by Professor Rehman who assessed Mr Theuri on 4 November 2025. He found that as at that date Mr Theuri had moderate situational anxiety disorder of fear of injury and severe generalised anxiety. These symptoms were likely to resolve in three to four months with therapy, and in ten to 12 months without therapy.

Finally, there was a positive pre-sentence report. Its author stated that there was a low risk of re-offending by the appellant and a medium risk of harm to the public. The appellant had expressed genuine remorse and took responsibility for his actions. He was in employment and he lived with his 65 year old mother and his 12 year old son, both of whom would be impacted by him serving a custodial sentence. He had expressed good motivation to engage with the Probation Service as part of a rehabilitation activity requirement, and to do unpaid work as part of a community order. The author of the report therefore proposed a 12 month community order.

The judge summarised Mr Theuri's evidence as to his injuries. He also said that that he had had regard to Dr Kim's report and, in particular, the statement that "It is expected that Mr Theuri will have some degree of lasting functional impairment of his right ankle". The judge said that he was satisfied to the criminal standard that this was a case in which Mr Theuri had been caused permanent, irreversible injury to his ankle, which had had, and would continue to have, the effects mentioned in category 1 of the sentencing guideline.

The judge went on to note that whilst there was a prospect that the injury to the nose may resolve, that would require surgery; and he noted Dr Kim's evidence that the procedure did not guarantee complete resolution of the symptoms and carried recognised risks.

The judge said that he had considered R v Hayes [2025] EWCA Crim 750, but that each case has to be considered on its own facts. He reiterated that the court had heard evidence from the victim about the effect of his injuries, as well as what the judge described as a "wealth of medical evidence". He was satisfied that the offending fell into category B1 on the sentencing guideline, the category starting point for which is three years' custody, with a range of two to four years.

The judge noted that the appellant was 43 years old and that he had one previous conviction for a public order offence in 2009. He said that he would not treat this as aggravating the offending, and that there were no statutory aggravating factors, although he did consider this to be a particularly nasty offence, given that the assault had continued when Mr Theuri was prone and vulnerable on the ground. He said that he had taken this into account.

As far as mitigation is concerned, the judge noted that there were various references which spoke highly of the appellant. He noted that the appellant had suffered various bereavements and said that he bore in mind the contents of the pre-sentence report and the observations as to rehabilitation. He also took into account the effect which incarceration would have on the appellant's son and his mother, and the appellant's letter to the court. The judge accepted the regret and remorse which the appellant had expressed.

The judge arrived at a sentence of 33 months' custody, and then made a reduction of one third to reflect the appellant's guilty plea. He then considered whether the custodial sentence should be suspended. He said that he had thought long and hard about the persuasive arguments advanced by Mr Ryle in favour of suspending the sentence. However, he went on to say:

On behalf of the appellant, in conspicuously able submissions, Mr Ryle argues that the sentence of 22 months' imprisonment which was imposed was manifestly excessive and that the judge erred in two respects: first, he was wrong to classify the harm suffered by Mr Theuri as category 1 on the Sentencing Guideline; and second, that he should have suspended the sentence.

As far as the first point is concerned, Mr Ryle argues, both orally and in writing, that the judge could not be satisfied to the criminal standard that the injuries to Mr Theuri were permanent and irreversible, as required for category 1 offending. Even if there were permanent or irreversible effects, they were not of an order which would put the case into category 1 on the Sentencing Guideline. He points out that the notes of Mr Theuri's treatment and assessment record a steady recovery of the ankle and that, by 18 June 2024, the orthopaedic surgery team noted that the fracture was healing and that the patient was walking without the boot. There was a loss of muscle bulk to the right calf, but the plan included advice to return to normal activity and physiotherapy.

Mr Ryle points out that Dr Kim's report was based solely on the medical notes; that he was not involved in Mr Theuri's treatment and nor had he examined him. He did not specifically mention any assessment after 18 June 2024. His prognosis was based on the type of injury sustained, rather than direct experience of the particular patient and his injury. Mr Ryle argues that the judge therefore ought not to have attached any or any significant weight to Dr Kim's statement that it was expected that Mr Theuri would have some degree of lasting functional impairment of his right ankle.

Mr Ryle notes that as far as the nasal injury is concerned, Dr Kim went no further than to say that there was no guarantee of complete resolution and that the surgery carried recognised risks. Dr Rehman's evidence was that the psychological effects were not permanent or irreversible. On the contrary, they would resolve themselves over time. This would be more rapid if Mr Theuri undertook therapy.

Moreover, Mr Ryle submits, the judge failed to take sufficient account of the fact that the Sentencing Guideline proceeds on the basis that the victim has suffered really serious harm, and that the criteria set out in the guideline should be seen in this context. He reminds us that this point is made in the Guideline itself, which states that all cases will involve really serious harm, and that the court should assess the level of harm caused with reference to the impact on the victim.

In addition, Mr Ryle relies on a comparison with the facts in Hayes, where a different constitution of this court noted that serious harm is inherent in this type of offence and found on the facts of that case that harm was not even in category 2.

Mr Ryle also says that the judge failed to factor in the required balancing exercise where more than one harm factor is present, including factors indicating lesser harm.

Mr Ryle's overall submission was that the judge should have found that the appellant's offending was at the upper end of category 3, or the lower end of category 2 for harm on the Sentencing Guideline.

As far as Mr Ryle's second ground of appeal is concerned, he submits that the judge refused to consider suspension of the custodial term. In finding that the seriousness of the offence meant that appropriate punishment could only be achieved by immediate custody, the judge placed undue reliance on the seriousness of the offence and did not properly consider the factors which pointed towards a suspended sentence. Moreover, as Mr Ryle submitted under ground 1, the judge's view of the seriousness of the offence was flawed, at least as far as the application of the Sentencing Guideline was concerned.

We agree that this was not category 1 offending. The categories in the Guideline are categories of really serious injury. The third category 1 factor which says "offence results in a permanent irreversible injury or condition which has a substantial and long term effect on the victim's ability to carry out their normal day to day activities or on their ability to work" should be read in the context of the second factor: "injury results in physical or psychological harm, resulting in life-long dependency on third party care or medical treatment". Moreover, category 2 contemplates grave injury or offending which results in a permanent, irreversible injury or condition not falling within category 1 – i.e. that there are permanent effects, but not of the order contemplated by category 1.

We consider that the injury to Mr Theuri's ankle, and/or the combination of his injuries, including his psychological injuries, were sufficiently serious to be categorised as “grave” for the purposes of category 2 on the Sentencing Guideline. The judge was also fully entitled to take account of Mr Theuri's evidence of his continuing symptoms nearly two years after the incident, and of Dr Kim's evidence as to the prognosis, and to find that Mr Theuri would suffer permanently with physical symptoms, albeit we agree with Mr Ryle that these would not be of the order which would put the offending into category 1.

There is no dispute that the offending falls withing category B culpability, but we agree with the judge that this was a nasty attack; that it continued when Mr Theuri was on the ground and vulnerable; that it was unprovoked; that it took place in the workplace and, ironically, in the course of the appellant's work as a security guard, all of which moves the offending upward on the range.

The starting point for category 2B offending is two years' custody, with a range of one to three years. In our view, the aggravating features of the case are cancelled out by the mitigating features – principally the appellant's remorse and the evidence of his generally good character. This brings that sentence down to 24 months' custody after a trial.

With a one third reduction for the guilty plea, we consider that the custodial term should have been 16 months, rather than 22.

Like the judge, we have carefully considered whether this sentence should be suspended, having been reminded of the sentencing guideline on the imposition of custodial and community sentences. We agree that there is a case to be made in favour of this course, on the basis advanced by Mr Ryle. The appellant has a limited history of offending. The pre-sentence report is positive on the issue of prospects of rehabilitation, as we have noted. There is genuine remorse, and the appellant pleaded guilty at the first opportunity.

However, having weighed the various factors, we have come to the conclusion that the seriousness of the offence, involving as it did a nasty episode of violence which resulted in category 2 really serious harm and continuing impairment to the victim, is such that appropriate punishment can only be achieved by immediate custody.

We therefore allow the appeal to the extent that we quash the sentence of 22 months' imprisonment and substitute a sentence of 16 months' immediate imprisonment.