R v Musgrove [2025] EWCA Crim 1202:
Gambling Disorder, ADHD and the Duty to Apply the Mental Disorders Sentencing Guideline

1. Introduction

This commentary examines the judgment of the Court of Appeal (Criminal Division) in R v Musgrove [2025] EWCA Crim 1202, a sentencing appeal arising from a substantial course of blackmail offences committed by a young adult with a diagnosed severe gambling disorder and ADHD.

The case is significant because the Court of Appeal:

Explicitly treats gambling disorder as a psychiatric illness sitting alongside more “traditional” addictions such as drugs and alcohol.
Clarifies that where such a disorder is causally linked to the offending, the Sentencing Council guideline on “Sentencing offenders with mental disorders, developmental disorders, or neurological impairments” must be actively engaged with.
Emphasises that expert psychological evidence cannot be sidestepped without “compelling reasons”, and the sentencer must clearly explain any decision not to treat it as reducing culpability.
Demonstrates concretely how a failure to apply that guideline amounts to an error in principle, justifying appellate intervention and a reduction in sentence.

The decision therefore establishes an important marker for the future sentencing of offenders whose criminal conduct is driven or significantly shaped by behavioural addictions such as gambling, especially where there is also neurodiversity (here, ADHD).

2. Factual Background and Procedural History

2.1 The offending

The appellant, Musgrove, was aged 20–21 at the time of the offending and sentence and of previous good character. He pleaded guilty to sixteen counts of blackmail, with a further 38 similar offences taken into consideration (“TICs”). In total there were 54 victims.

The offences were committed between August 2023 and July 2024. The pattern was broadly similar across victims:

Musgrove contacted individuals, often via social media.
Some were persuaded to send money on the pretext of gambling for profit.
Others were falsely informed that they had outstanding drug debts which had to be paid.
When they resisted, he used threatening and coercive messages, including:
- Threats to reveal fictitious drug debts to employers or family.
- Threats to damage their homes, supported by screenshots of their addresses.
- Direct threats of violence, e.g. “I'm going to cut your legs off mate and feed them to my fish” and references to harm while a victim’s child was in the house.

The total financial loss was approximately £9,195 (£6,235 on the indictment and £2,960 on TICs). Two victim personal statements graphically described:

Long-lasting mental health effects, anxiety and shame at being duped.
Fear of leaving home and serious financial stress after borrowing to meet the blackmail demands.

2.2 Persistence despite arrest and bail

An aggravating feature was the continued offending after arrest:

First arrest: 5 November 2023 (six offences already committed); released on bail.
Second arrest: 21 April 2024 (a further five offences); released on bail.
Third arrest: 5 August 2024, following a further five offences.

The 38 TICs overlapped with this timeline, with:

4 TICs before the first arrest,
14 between the first and second arrests, and
20 between the second and third arrests.

Over half of the total offending occurred after Musgrove had already been arrested on two occasions, which the sentencing judge regarded as highly aggravating and demonstrative of entrenched criminality for gain.

2.3 Sentencing at first instance

On 25 November 2024, in the Crown Court at Reading, His Honour Judge Nawaz sentenced Musgrove to 3 years and 4 months (40 months) detention in a young offenders’ institution on each of the 16 counts, to run concurrently. The court was told there were no offence-specific guidelines for blackmail (a point the Court of Appeal does not revisit).

The sentencing judge reasoned as follows:

He identified a notional sentence of 7 years (84 months) custody as the appropriate level had Musgrove been convicted after trial, taking into account both the indictment offences and the TICs.
He then reduced this by 24 months to 5 years (60 months) to reflect:
- Musgrove’s age,
- his personal mitigation and positive references, and
- his gambling difficulties (though treated essentially as personal mitigation).
He applied a one-third discount for the timely guilty pleas (which were accepted as genuine and early), reducing 60 months to 40 months.

In his remarks, the judge asserted that:

The offending was planned and considered, with a devised method for intimidation.
Although Musgrove was “in the throes of a gambling disorder”, this was “very different from somebody who has… an addiction to drugs”, emphasising that gambling was something “you undertake voluntarily”.
He did not consider Musgrove to lack maturity.

Musgrove appealed the sentence with leave of the single judge.

3. Summary of the Court of Appeal’s Judgment

The appeal was brought on a single ground: that the sentencing judge erred in failing to treat Musgrove’s severe gambling disorder (and associated ADHD) as an addiction/mental disorder requiring application of the Sentencing Council guideline on offenders with mental disorders, developmental disorders or neurological impairments. As a result, it was said that the judge:

Failed to consider whether Musgrove’s culpability should be reduced.
Failed to consider whether imprisonment would have an increased impact.
Imposed a sentence that was therefore wrong in principle and/or manifestly excessive.

The Court of Appeal:

Held that gambling disorder is a psychiatric illness, recognised in DSM-5 and “sitting alongside the traditional addictions” such as drugs and alcohol.
Found that the expert psychological report, which described a severe gambling disorder significantly impairing rationality and control, established a strong causal connection between the disorder and the offending.
Held that, in these circumstances, the sentencing judge was required to engage with and apply the Sentencing Council’s mental disorders guideline, especially paras 13 and 14:

Para 13: The sentencer must consider expert evidence but is not bound by it; it may be departed from only if there are compelling reasons.

Para 14: The sentencer must clearly state:

whether culpability is reduced, and to what extent; and

if expert opinion is not followed, the reasons for not doing so.

The Court found:

There were no compelling reasons to discount the expert’s opinion.
The judge had in effect downgraded the gambling disorder to mere personal mitigation, rather than treating it as a mental disorder potentially reducing culpability.
The judge also appears to have overlooked Musgrove’s voluntary attendance at a gambling support group (Gamline) in May 2024 as an indicator he was trying to address his problem.

Concluding that the judge erred in principle and gave insufficient reduction for Musgrove’s neurodiversity and addiction, the Court of Appeal:

Reduced the notional after-trial sentence by an additional 6 months (from 60 months to 54 months) to reflect the correct application of the mental disorders guideline and the causal impact of the gambling disorder and ADHD.
Applied the same one-third discount for guilty pleas to 54 months, producing a final sentence of 36 months (3 years).
Quashed the original 40-month sentences and substituted concurrent sentences of 3 years’ detention in a young offenders’ institution.
Clarified that, given Musgrove’s age at conviction, the sentence must formally be recorded as detention in a young offenders’ institution rather than “imprisonment”.

4. Detailed Analysis

4.1 The legal framework: Guidelines, culpability and mental disorder

Two core elements of the legal framework underpin the judgment:

The general principles of sentencing appeals, namely that the Court of Appeal may interfere if a sentence is wrong in principle or manifestly excessive.
The Sentencing Council guideline on “Sentencing offenders with mental disorders, developmental disorders or neurological impairments”, especially section 2, paras 13–14.

Although the judgment notes that there were said to be no offence-specific guidelines for blackmail before the judge, the appeal turns not on the blackmail guideline but on the generic mental disorders guideline, which applies to all offences where relevant.

(a) The mental disorders guideline: key duties

The guideline imposes several structured duties on the sentencing judge where a mental disorder, developmental disorder or neurological impairment is in play:

Identify whether the disorder is present, supported by appropriate evidence (often expert).
Assess the degree of connection between the disorder and the offending behaviour.
Consider whether culpability is reduced by that disorder, and if so, by how much.
Consider the impact of custody on the offender—whether imprisonment will have a disproportionately severe effect because of the condition.
Engage with expert evidence:
- The sentencer is not bound by experts but must consider their evidence.
- The court may depart from that evidence only if there are compelling reasons to do so (para 13).
Give clear reasons:
- The judge must explicitly state whether (and to what extent) culpability is reduced (para 14).
- If the expert view is not followed, the judge must explain why.

R v Musgrove focuses on the judge’s omission to follow this structure, especially paras 13–14.

4.2 Expert evidence: Gambling disorder and ADHD

The psychological report by Dr Gaskell was central. It concluded that:

Musgrove had a severe gambling disorder at the time of the offences.
The disorder “significantly alters thinking, attention, decision making and behaviour”.
It was “the main cause of his index offences” and:

“Without the gambling disorder I do not believe that he would have committed the offences.”

Dr Gaskell also emphasised that:

Gambling disorder is recognised in DSM-5 and “sits alongside the traditional addictions” such as substance misuse.
There is a strong statistical overrepresentation of ADHD among those treated for gambling disorder (up to 25% in some research).
Symptoms of ADHD (impulsivity, impatience, high reward sensitivity, proneness to boredom, etc.) can act as pathways into gambling addiction.
Gambling disorder is a “chronic relapsing psychiatric illness” with a significant effect on rationality and control capacity.

The psychiatrist’s ultimate opinion was that the offences:

“have all been carried out in the context of this psychiatric illness, which has significantly impaired his rationality and control capacity.”

In other words, the report did not suggest a tangential or background issue, but a direct and significant causal link between Musgrove’s psychiatric condition and his offending.

4.3 The sentencing judge’s approach – where it went wrong

The sentencing judge accepted that Musgrove had a gambling disorder but then made two critical moves:

He distinguished gambling disorder from “traditional” addictions such as drug addiction, emphasising that gambling is something undertaken voluntarily.
He appears to have treated the gambling problem as merely a form of personal mitigation (alongside age and character) rather than a psychiatric illness capable of reducing culpability under the mental disorders guideline.

He further concluded that Musgrove did not lack maturity and that the offending had been deliberately planned and carefully executed, which is relevant to culpability but does not by itself answer the question of whether a psychiatric disorder has impaired rationality or self-control.

Crucially, the judge:

Did not expressly engage with the mental disorders guideline.
Did not set out any structured analysis of whether culpability was reduced.
Did not explain why he was effectively declining to follow the expert opinion that the disorder was the main cause of the offences.
Appears partly to have overlooked Musgrove’s voluntary engagement with Gamline in May 2024, which pointed away from sheer indifference and towards a person struggling with a relapsing addiction.

The Court of Appeal therefore held that the sentencing judge had failed to apply the guideline properly, and in doing so had erred in principle.

4.4 The Court of Appeal’s reasoning: gambling disorder as psychiatric illness

The Court carefully analysed the expert evidence and DSM-5 nomenclature. It expressly accepted that:

Gambling disorder is at the severe end of a continuum of gambling harm.
It is a psychiatric illness, not merely a bad habit or lifestyle choice.
It is properly treated as analogous to other recognised addictions.

The Court inferred that the psychologist’s reference to “traditional addictions” meant drug and alcohol addictions and noted that the sentencing judge had tried to distinguish gambling from these on the ground of voluntariness. The Court rejected that distinction:

While initial engagement with gambling may be voluntary, the disorder itself—once developed—is a chronic, relapsing psychiatric illness that can significantly impair control, rationality and decision-making.
The Court saw no compelling reasons to depart from the expert view that this was the main cause of the offending.

Accordingly, the guideline had to be engaged:

Para 13: The expert opinion had to be considered, and could only be rejected on compelling grounds. None were identified.
Para 14: The judge needed to clearly state whether (and how far) culpability was reduced by the disorder, and if not, why not, especially in light of the expert evidence. He had not done so.

On that basis, the Court concluded:

“We conclude that the judge erred in principle. Insufficient reduction was given to reflect the appellant's neurodiversity and addiction.”

4.5 Culpability reduction and sentence recalculation

The Court did not abandon the original judge’s core assessment of the seriousness of the offending:

Multiple victims (16 on indictment, 38 TICs).
Persistent, repeated conduct over nearly a year.
Continuation after arrest on two separate occasions.
Serious threats of violence and significant psychological harm.

It accepted that a notional after-trial sentence of 7 years (84 months) for the offending, treated in the round, was appropriate. It also accepted that the original judge had already given 24 months’ reduction for non-disorder mitigation (age, character, some recognition of gambling problems).

Where the Court differed was in the extent of mitigation warranted by properly recognising the psychiatric impact of the gambling disorder and ADHD. It therefore:

Retained the 84-month starting point.
Retained the original 24-month reduction already given by the judge for general mitigation, leaving 60 months.
Applied a further 6-month reduction for the under-recognised impact of the psychiatric disorder, reducing 60 to 54 months.
Applied the one-third discount for guilty pleas to 54 months, producing 36 months (3 years).

This is a subtle but important message:

The Court did not view the gambling disorder as eliminating culpability or making custody inappropriate—it recognised that Musgrove still had significant agency and that the offences were serious.
But it did hold that properly applying the guideline required a meaningful further reduction to reflect the diminished control and rationality, and the increased hardship of custody.

4.6 Correction of the sentence form: young offenders’ detention

Finally, the Court noted that Musgrove was 18 at the date of conviction. The original sentence had been recorded as one of “imprisonment”. The Court clarified that the correct legal form was detention in a young offenders’ institution, and the order was recorded accordingly.

Though a technical point, this highlights the continuing attention appellate courts pay to age-related custodial regimes, especially where developmental factors and mental disorders are in issue.

5. Impact and Significance

5.1 Recognition of gambling disorder as a sentencing-relevant psychiatric illness

The central precedent value of R v Musgrove lies in its treatment of gambling disorder:

It explicitly endorses the medical/psychiatric understanding of gambling disorder as a chronic relapsing psychiatric illness.
It treats gambling disorder as effectively on a par with substance addictions for sentencing purposes when it:
- Is diagnosed at the severe end of the spectrum, and
- Has a demonstrable causal impact on the offending.
It rejects simplistic arguments based on voluntariness (“you chose to gamble”) as a reason to discount the disorder; instead, it looks at how far the illness has impaired control and rationality.

Given the prevalence of gambling-related offending (fraud, theft, blackmail, etc.), this clarification is likely to be regularly invoked in future sentencing hearings.

5.2 Strengthening of the mental disorders guideline in practice

The judgment reinforces several practical requirements for judges dealing with offenders with mental disorders:

Mandatory engagement: Where credible evidence of a mental disorder is put forward, especially expert evidence, the guideline must be consulted and applied.
Structured reasoning: Judges must clearly:
- Determine whether there is a sufficient connection between the disorder and the offending.
- State whether culpability is reduced and by how much.
- Address whether custody will have an increased impact on the offender.
Expert evidence cannot be brushed aside: If an expert says a disorder is the main cause of the offending and significantly impairs control, a judge may reject that only if there are compelling reasons, which must be explained.
Personal mitigation vs culpability: The judgment draws an implicit but important distinction between:
- Treating mental disorder as mere personal mitigation (like character references), and
- Recognising that it may reduce culpability itself, fundamentally altering the starting point.

R v Musgrove therefore operates as a practical enforcement of the mental disorders guideline, making clear that failure to follow its structure can amount to an error in principle warranting appellate intervention.

5.3 Neurodiversity and co-morbidity

The case is also notable for its reference to ADHD as part of Musgrove’s neurodiversity, and the way ADHD symptoms (impulsivity, high reward sensitivity, boredom) can act as a gateway to gambling addiction.

This contributes to a broader trend in sentencing:

Neurodevelopmental conditions (ADHD, autism spectrum conditions, etc.) are increasingly recognised not only as background factors but as conditions that can:
- Increase vulnerability to other disorders (e.g. addiction).
- Influence decision-making and risk-taking behaviours.
Where there is co-morbidity (e.g. ADHD and gambling disorder), the combined effect on behaviour and culpability may be greater than each condition considered in isolation.

The Court’s acknowledgment of ADHD in the causative pathway underscores that sentencing must now regularly address neurodiversity in a structured way, not as an afterthought.

5.4 Sentencing outcomes: serious crime, still serious punishment

It is important to note that, even with proper recognition of Musgrove’s psychiatric illness, the Court of Appeal still upheld:

A high starting point (7 years after trial).
Substantial immediate custody (3 years after guilty plea).

This underscores an important balancing principle:

Mental disorder can reduce culpability and justify a lower sentence, but it does not necessarily make custody inappropriate where the offending:
- Is serious and prolonged;
- Involves multiple victims and deliberate threats; and
- Continues despite arrest and bail.

The case therefore illustrates a measured approach: serious crimes driven by mental disorder still attract significant custodial sentences, but at a level that recognises the offender’s impaired control and the greater burden custody may impose.

6. Complex Concepts Simplified

6.1 What is blackmail in this context?

Blackmail is the offence of making an unwarranted demand with menaces with a view to gain or with intent to cause loss. In Musgrove’s case, the “menaces” were threats of violence, property damage, and reputational harm (e.g. informing employers or family of supposed drug debts).

6.2 What are TICs (offences taken into consideration)?

At sentencing, a defendant can ask the court to consider additional admitted offences (TICs) without a separate prosecution or sentence for each. The effect is:

The overall sentence reflects the total criminality, including TICs.
The TICs are effectively “cleared up” without further charges.

In this case, Musgrove had 38 TICs of blackmail, broadly similar to the indictment counts.

6.3 What is meant by “culpability” in sentencing?

Culpability is about how blameworthy the offender is. Factors that affect culpability include:

Planning and premeditation.
The offender’s role (leader, follower, coerced participant etc.).
Mental state and capacity for understanding and control.

A mental disorder can reduce culpability if it:

Impaired the offender’s ability to think rationally about their actions, or
Significantly reduced their self-control, or
Distorted their decision-making in a way directly linked to the offence.

6.4 How is mental disorder different from ordinary mitigation?

Ordinary mitigation refers to factors like:

Good character.
Remorse.
Young age or difficult background.

These may justify reducing the sentence within the same culpability category. But a mental disorder that meets the guideline’s criteria can do more: it can change the starting point by placing the offender in a lower culpability bracket altogether.

6.5 What is a “psychiatric illness” in this context?

A psychiatric illness is a recognised mental health condition, usually diagnosable under standard classification systems such as DSM-5. In Musgrove:

Gambling disorder is recognised in DSM-5 as a behavioural addiction.
It is characterised by persistent, problematic gambling leading to significant impairment or distress.
At its severe end, it can significantly distort thinking, priorities, and self-control.

6.6 What is a “young offenders’ institution”?

A young offenders’ institution (YOI) is a custodial facility for younger offenders (typically those under a certain age at conviction). The regime is meant to be more tailored to:

Developmental needs, and
Rehabilitation and education.

In Musgrove, the Court corrected the record to confirm that his sentence was one of detention in a young offenders’ institution, not adult imprisonment, reflecting his age at conviction.

7. Conclusion

R v Musgrove [2025] EWCA Crim 1202 is an important sentencing authority at the intersection of serious acquisitive crime and behavioural addiction. Its key contributions can be summarised as follows:

It confirms that severe gambling disorder is a psychiatric illness that can materially reduce culpability where it has a sufficient causal connection to the offending.
It insists that sentencing judges must rigorously apply the Sentencing Council guideline on offenders with mental disorders, especially:
- Considering and engaging with expert evidence, and
- Giving clear reasons where they choose not to follow it.
It treats the failure to apply that guideline, and the downgrading of gambling disorder to mere personal mitigation, as an error in principle justifying a reduction in sentence.
It illustrates a balanced approach: even with reduced culpability due to addiction and ADHD, serious, persistent blackmail still attracts substantial custody, but at a lower level than if full culpability were assumed.
It underscores the growing importance of neurodiversity and co-morbid conditions (such as ADHD) in assessing both culpability and the impact of imprisonment.

For practitioners, the message is clear: where behavioural addictions like gambling are supported by robust psychiatric evidence and closely linked to the offending, they must be dealt with through the formal structure of the mental disorders guideline, not treated as an optional gloss on an otherwise “normal” sentencing exercise. Failure to do so now carries a real risk of appellate correction.

R v Musgrove [2025] EWCA Crim 1202: Gambling Disorder, ADHD and the Duty to Apply the Mental Disorders Sentencing Guideline