Court of Appeal: ASD Diagnosis Leads to Reassessment of Dangerousness

22nd May 2025

R v MW

The Court of Appeal considered fresh evidence, in the form of psychiatric reports confirming a diagnosis of ASD, in reducing the sentence and overturning a finding of dangerousness in respect of a young person (aged 18 at sentence) convicted of terrorism offences (aged 16 at time of commission). 

Details

On 14.09.2023, the applicant MW, then aged 18, was convicted of three counts of possessing information contrary to s58(1)(b) of the Terrorism Act 2000 as well as three counts of dissemination of terrorist publications, contrary to s2(1) and 2(2)(e) of the Terrorism Act 2006. He had been 16 years old at the time of the commission of the offences. 

The documents had included materials on the manufacture of explosives and  improvised firearms, as well as more than 100 documents in an online “library”, including terrorist manifestos.

The judge assessed MW as dangerous and he was accordingly sentenced to an extended determinate sentence, comprised of a six year custodial term and an extended license period of one year. He was required to comply with the notification requirements for a period of 15 years. At sentence, the judge referred to MW’s demeanor in evidence as “cold” and “calculating” (paragraph 22), and lacking remorse. He was also said to be mature. The reduction in sentence for his youth was therefore reduced to 25%. 

MW initially appealed against sentence on the grounds that:

  1. an insufficient reduction for age was given;
  2. the judge was wrong to characterise the offending as intentional rather than reckless;
  3. insufficient regard was given to the delay in bringing the charge and trial.

He renewed his application to appeal following refusal by the single judge, advancing a fourth ground, alongside an application to introduce fresh evidence – a psychiatric report and an addendum psychiatric report. The conclusion of these reports – that he had ASD – had not been known at the time of conviction and sentence or by the single judge and it was submitted that had the judge known at the time of sentence, the sentence would have been reduced in line with the guidelines on sentencing offenders with mental disorders. Additionally, it would no longer have been warranted to include in considerations of sentence MW’s “cold” or “calculating” demeanor, both of which were potential misinterpretations of MW’s ASD and his subsequent presentation at trial. There was also no basis, at the date of sentence, to conclude that MW posed a significant risk to members of the public. 

The Crown argued that the fact of MW’s ASD would have had little impact on the sentencing exercise and the sentence passed was neither wrong in principle nor manifestly excessive; the judge had been entitled to form each of the views that she had and to reduce the sentence by 25% taking into account the circumstances of the offending and the detailed PSR that had been received. In particular, the judge’s contention that “anyone who can encourage acts of violence has to be a very obvious danger to the public” (paragraph 43) was not something that would be materially changed by a diagnosis of ASD. 

The Court of Appeal allowed the appeal, admitting the fresh evidence and overturning the judge’s finding of dangerousness as well as reducing the term of imprisonment to five years. In doing so, it found that:

  1. had the evidence been available to the judge at the time of sentence, she would have had to approach the reduction for age more generously (paragraph 50);
  2. the judge’s view of MW’s presentation had played a significant part in her decision on dangerousness. The conclusions she had come to about his demeanor would not have been fairly open to her had she had the benefit of the fresh evidence (paragraph 51);
  3. Absent a conclusion that MW was cold and emotionless in evidence, it is unlikely that the conclusion as to dangerousness would have been reached. 

Commentary

This case is a significant reminder of the need for youth justice lawyers and practitioners to scrutinise findings of dangerousness, particularly where a young person may be neurodivergent. It highlights the risk of courts misinterpreting behaviours linked to conditions such as ASD, and reinforces the importance of timely expert evidence when assessing future risk under the dangerousness test.