Diminished and Dangerous
British sentencing guidelines' obsession with culpability is risking public safety and sending innocent people to their deaths
Valdo Calocane, the Guinea-Bissau born perpetrator of the 2023 Nottingham attacks, was sentenced to an indefinite hospital order under the Mental Health Act on the 24th of January 2024 by Nottingham Crown Court. He had stabbed two students, Barnaby Webber and Grace O’Malley-Kumar, to death on the street. He then attacked a 65-year-old school caretaker, Ian Coates, on his way to work, killing him, before stealing his van and driving it into several nearby pedestrians, of whom another was put into critical condition.
Mr Justice Turner of the Crown Court accepted that Calocane’s psychosis had reduced his culpability sufficiently for the prosecution to accept pleas of manslaughter by reason of diminished responsibility. He then said, ‘But all other things are not equal. I consider that, regardless of the level of your personal responsibility, you were and remain dangerous.’ The prosecution’s own psychiatric expert, Professor Blackwood, had also established that ‘there is a significant risk to members of the public of serious harm occasioned by the commission of further offences if his psychosis is not appropriately treated’, and that how complete any recovery might be was not known.
The evidence that was used to argue for leniency could equally justify a case for indefinite caution — the court, in fact, accepted both. The sentencing framework, however, had no language for holding the two conclusions at once. The hospital order removed the case from the criminal sentencing framework, placing the public protection problem in the hands of a different institution on different terms.
Calocane’s case exposes the contradiction in stark terms, but it is by no means an isolated example. In R v Gomez [2025] EWCA Crim 342, this contradiction appeared again within the ordinary adult sentencing framework itself. A Crown Court judge treated ADHD, anxiety and depression as mitigation for an offender with fourteen convictions for twenty-two offences, including a previous sentence for GBH with intent. Despite a sustained knife attack on an intimate partner, strangulation, breach of a restraining order and a clear pattern of escalating violence, no dangerousness finding was made and no extended sentence imposed. The Solicitor General referred the sentence as unduly lenient, and the Court of Appeal increased it from four years to five — but only because he thought the offence itself deserved greater punishment, and not because he thought the offender posed an ongoing danger to the public. The Court accepted that he had calmed down, to a degree, in custody and was engaging more constructively with the prison regime.
This is obviously not the same as concluding that the underlying conditions had disappeared, or that the disposition that they produced had fundamentally changed. At most, the evidence suggested that the risks may have been temporarily lower and better managed in a tightly controlled institutional environment. If the conditions were serious enough to reduce culpability at the time of offence, the framework provides no account of when or why they stop mattering for public protection.
Stories such as these baffle the public and have eroded trust in the justice system in record time. Cases like these are maddening, and faith in the system declines with every new example. Understanding how this could possibly happen requires a brief detour into how sentencing works. Courts proceed in stages. First, they assess the seriousness of the offence (the harm caused and the offender's culpability) to reach a starting point. Second, they adjust that starting point using aggravating factors, which push the sentence up, and mitigating factors, which push it down. Mental disorder, cognitive impairment, and emotional dysregulation enter at the second stage. They enter as mitigations: diminished capacity, diminished blameworthiness, lighter sentence. This describes the default pathway for adult offenders — cases involving youth or extreme mental illness follow different routes, as discussed elsewhere in this article.
Hang on, though. An offender with low impulse control, poor emotional regulation, a personality disorder, or a cognitive profile that impairs their capacity to reason about consequences is — by the very characteristics the framework treats as mitigating — less likely to be deterred by punishment, less amenable to rehabilitation, and more likely to reoffend. If sentencing is supposed to protect the public, shouldn’t these characteristics push the sentence up rather than down?
The answer, of course, is yes. On paper, the current sentencing framework should be able to address these concerns; instead, such factors are taken as mitigating — chiefly due to a lack of clarity in the guidelines.
The Criminal Justice Act 2003 listed five purposes of sentencing — now restated virtually unchanged in section 57 of the Sentencing Act 2020 — punishment, crime reduction, rehabilitation, public protection, and reparation. It does so without ranking them or explaining how to resolve conflicts between them. Public protection is the Cinderella of this framework: officially invited, consistently side-lined. The five purposes pull against each other constantly. The guidelines built on this foundation inherit the contradiction without resolving it. Pair this with the tendency amongst the establishment to view mental health conditions as grounds for endless patience and conferring irreproachable victimhood on their sufferers (or, as Neil O’Brien has discussed, the worrying tendency to avoid addressing dangers posed by individuals with mental health conditions in particular communities because of ‘anti-racist’ concerns), and we have a recipe for incredible injustice and massive risk to public safety.
The public has been outraged by this state of affairs for years now, and correctly identifies it as rotten to the core. Look at the close parallel offered in the youth justice system last week in the grim case at Southampton Crown Court that met with furore. Judge Nicholas Rowland sentenced three teenage boys — convicted of gang-raping two schoolgirls on separate occasions, filming both attacks, using a knife in the second — to youth rehabilitation orders. He cited their low IQs, ADHD, anxiety, and limited understanding of consent. He told them: ‘I have to think how likely you are to do serious things again, and I need to make sure you do not do serious things again in the future.’ He then sent them home. The characteristics he treated as grounds for leniency are precisely the characteristics any sensible criminologist would identify as predictors of serious reoffending. The judge saw the public protection problem. The framework gave him no clear route from recognising the danger to choosing to do something about it. The Youth Sentencing framework Judge Rowland was obliged to apply does not include the five-purpose structure that governs adult sentencing. Its primary aim is to prevent reoffending. Even where prevention of reoffending is the stated primary aim, the framework provided no mechanism for translating acknowledged risk into protection measures.
North of the border, the Scottish Sentencing Council introduced guidelines in January 2022, making rehabilitation the primary consideration for all offenders under twenty-five, on the grounds that the human brain is not fully mature until the mid-twenties — despite, according to critics of the proposal, a majority of consultation respondents rejecting it. In April 2023, a Scottish judge sentenced Sean Hogg to 270 hours of community service for repeatedly raping a thirteen-year-old, saying an adult over twenty-five would have received four to five years. The brain immaturity which is used to justify leniency is the same brain immaturity that any risk assessment would flag as an aggravating factor. This absurdity also met with derision among much of the Scottish public.
The most straightforward path to restoring public faith in the sentencing system would be to clear the ambiguity left in the 2003 Act and give public protection real and proper consideration.
There is a serious objection to this approach, and it deserves a proper hearing. Retributive justice requires that we sentence people for what they did, not what they might do. Reducing a sentence for reduced culpability is not merely permissible but required, however dangerous the person may be, so long as retribution is the primary consideration in sentencing. A system that sentences people for anticipated future acts has ceased, in any meaningful sense, to be sentencing at all.
That objection is entirely correct within a purely desert-based framework. It is available only to those prepared to accept its full implications: that public protection is simply not a purpose of sentencing. Retributive constraints are available only to those who accept public that public protection has no place in sentencing at all. The framework’s architects destroyed that answer the moment they wrote public protection onto the statutory list. You cannot invoke retributive constraints against the risk argument while simultaneously claiming public protection as a co-equal statutory purpose. The framework wants both. It provides no honest mechanism for having both. That is a failure of design.
Parliament has already accepted, in limited contexts, that desert and protection are distinct questions requiring distinct answers. Extended Determinate Sentences, introduced in 2012, allow courts to set a custodial term on desert grounds alongside an extended licence period of up to eight years, with release gated on a Parole Board finding that continued confinement remains necessary for public protection. Sentences of Particular Concern apply a similar structure to terrorism and the most serious child sexual offences. Parliament’s instinct in both cases was right.
But both tools require a formal dangerousness finding and are triggered by offence type – not by the scenario where mental health evidence simultaneously reduces culpability and elevates risk. And when that evidence produces a hospital order rather than a custodial sentence (as in Calocane’s case), the dangerous offender provisions are bypassed altogether. The Mental Health Act route removes the case from the sentencing framework entirely. The Sentencing Act 2020 disapplies the five-purposes framework where a hospital order is made — handing the protection question to the Mental Health Act provisions and ultimately the Mental Health Tribunal which operates on different principles and a different timetable. The cases where the problems of this inversion are most acute are, by design, the cases where the tools made available by Parliament are unavailable.
What is stopping us from taking a broader approach? Imprisonment for Public Protection, introduced by the same 2003 Act, was this logic in statutory form: a desert tariff, then an indeterminate tail, released only when the Parole Board was satisfied the risk was manageable. Only a few hundred cases per year were anticipated. By the time of abolition in 2012, it had been imposed on 8,711 people. As of September 2024, 1,095 had still never been released. Its architect, David Blunkett, expressed his own regret over this many years ago.
IPP was not wrong in principle. It failed on two specific counts. First, the indeterminate tail: a reviewable, fixed-term protection measure would have been more legitimate and more defensible. Second, and more fundamentally, the state demanded prisoners demonstrate their safety and then denied them the means of doing so. The courts looked dimly on that – even while comparable systems elsewhere in Europe survived legal challenges by offering greater therapeutic support. England built none of this. It announced a purpose and declined to fund it. We have been allergic to serious institutional investment in the detention and treatment of dangerous people since Enoch Powell began to close the Victorian asylums in the 1960s.
Reform then requires three things. First, rank the purposes of sentencing: desert primary, protection a close second but structurally separate, rehabilitation legitimate, incapable of overriding the primary purposes. Second, prune the mitigation framework accordingly. A condition that reduces moral blameworthiness operates at the culpability stage. At the protection stage, the same condition may justify significantly longer detention than the desert element alone. The characteristics that reduce culpability should actively trigger the protection measure, not merely excuse the crime. Finally, close the gap that EDS and SOPC leave open: the protection element must be available in cases where the mental health route has reduced the charge category or produced a hospital order, precisely the cases where the evidence of ongoing risk is most acute. But the deeper reform is not merely to plug gaps in an existing structure. It is to make the two-track principle universal: wherever diminished capacity is accepted as a mitigation, the same evidence must be assessed for its risk implications, and where it crosses the dangerousness threshold, a protection measure must follow, regardless of the offence category that mitigation helped reduce.
This requires investment that successive governments have refused to make: specialist settings, forensic risk review, a genuine institutional obligation to work toward release. And the burden at each review must sit with the state – to prove the risk remains unacceptable – not with the prisoner to prove they are safe.
The Criminal Justice Act 2003 built a framework on a contradiction it declined to resolve. The same characteristics that reduce culpability elevate risk; the framework registers one and is blind to the other. The system can recognise diminished culpability. It can also recognise danger to the public. It cannot do both at the same time. Ian Coates, Grace O’Malley-Kumar and Barnaby Webber were killed because that failure persisted. They will not be the last.
This article was written by Langley Curtis, a Pimlico Journal contributor. Have a pitch? Send it to submissions@pimlicojournal.co.uk.
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Very nice untangling of culpability and risk. Thank you. Interesting sidelight on the peculiar career of Saint Enoch, too.