No “Cliff Edge” at 18: Immaturity in Young Adult Sentencing and the Illegality of Imprisonment Under 21 (DYOI Required)

Commentary on R v Arshad [2026] EWCA Crim 296 (CA (Crim Div), 18 February 2026)

1. Introduction

This appeal concerned the sentence imposed on a young adult offender for affray and possession of an offensive weapon in a public place, arising from a planned group attack at the gates of a school in Slough. The appellant (Arshad) was 18 at the time of the offence (and 20 at sentence). His co-accused (Ahmad) was 17 at the time of the offence (and 20 at sentence). Both pleaded guilty.

The key issues on appeal were whether the Crown Court’s custodial term for affray was manifestly excessive given the appellant’s youth and immaturity (despite being just over 18), whether the sentencing judge sufficiently respected the basis of plea (that the bat was not used to inflict violence), and whether the sentencing exercise properly handled parity, delay, and the relationship between the affray sentence and the separate offensive-weapon count (including alleged “double counting”).

In addition, the Court of Appeal identified a distinct and decisive legal error: the sentences were pronounced as imprisonment, even though (as the Court held) section 227 of the Sentencing Act 2020 prohibits a sentence of imprisonment on a person aged under 21 when convicted, requiring Detention in a Young Offender Institution (DYOI) instead.

2. Summary of the Judgment

  • The Court of Appeal held that the Recorder was entitled to place the affray in category A1, but the case lay towards the lower end of that category because harm was borderline between categories 1 and 2.
  • The Court rejected the submission that there had been double counting in aggravating the affray to reflect the offensive-weapon element and overall totality.
  • The Court found the appellant’s sentence for affray (24 months’ custody at trial, reduced for plea) was manifestly excessive because the Recorder did not focus sufficiently on:
    1. the appellant being only just over 18 at the time of offending; and
    2. the appellant’s immaturity and susceptibility to peer pressure as described in the Pre-Sentence Report, together with the accepted basis of plea that he did not use the bat to inflict violence.
  • The Court substituted an appropriate sentence at trial of 18 months’ custody (equating to 12 months after full guilty plea credit), and maintained the same community requirements under the suspended sentence order.
  • The Court held the sentence was unlawful in form: pronouncing imprisonment for an offender under 21 at conviction contravened section 227 of the Sentencing Act 2020. The Court corrected both counts to DYOI (detention) sentences.

3. Analysis

3.1 Precedents Cited

R v Clarke [2018] EWCA Crim 185

The Court relied on R v Clarke [2018] EWCA Crim 185, quoting the principle at paragraph 21: “... reaching the age of 18 has many legal consequences, but it does not present as a cliff edge for the purpose of sentencing. So much has long been clear.”

In this appeal, that principle was operational rather than rhetorical. The Recorder treated the appellant’s being over 18 as a material differentiator when attempting to maintain parity with the youth co-accused, but the Court of Appeal held that sentencing must account for the reality that many 18–20 year olds remain developmentally and psychosocially immature. Clarke supported the Court’s conclusion that the sentencing judge must look beyond the formal age threshold and engage with evidence of maturity and culpability—especially where a Pre-Sentence Report speaks directly to immaturity, impulsivity, and susceptibility to pressure.

Sentencing Young People Overarching Guideline (as referenced)

Although not a “case”, the Recorder’s reference to the Sentencing Young People Overarching Guideline was central to the parity context. The Court noted the Recorder was “alive” to youth principles for Ahmad, but held he failed to apply an equivalent maturity-sensitive lens to the appellant, despite the appellant being only marginally older and demonstrably immature. The judgment thereby reinforces that youth-sentencing principles may remain relevant by analogy when sentencing young adults, particularly where maturity deficits are evidenced.

3.2 Legal Reasoning

(a) Guideline categorisation and seriousness

The Recorder placed affray in A1 (category 1 harm) on the basis of “serious fear/distress”, producing a higher starting point than the prosecution’s A2 approach. The Court of Appeal did not interfere with that classification, emphasising appellate restraint where a judge’s guideline assessment is permissible.

However, the Court refined how A1 should operate on these facts: this was an A1 case “very much towards the lower end”, given the absence of serious injury and the borderline nature of harm (consistent with the prosecution’s own analysis). In effect, the Court accepted A1 as the correct box but rejected a near-top-of-range outcome when the harm within the box was near the threshold.

(b) Double counting, totality, and the offensive weapon count

The appellant argued that aggravating the affray by reference to weapon possession “double-counted” because there was a separate offensive-weapon count. The Court disagreed, holding that some uplift in the affray sentence to reflect the overall criminality and totality was legitimate and did not constitute impermissible duplication.

The Court’s approach reflects a common sentencing reality: where multiple offences arise from the same incident, a judge may adjust the lead sentence to reflect the whole course of conduct, provided the final outcome remains proportionate and the separate count is not punished twice in substance.

(c) The decisive mitigation: young adult immaturity and role in the violence

The Court identified the “key consideration” as the appellant’s age and circumstances of offending, grounded in:

  • Age proximity to 18: the Court treated the appellant’s being “only just over 18” as a material feature, invoking R v Clarke [2018] EWCA Crim 185 to reject any “cliff edge” approach.
  • Pre-Sentence Report (PSR): the PSR described limited maturity, impulsivity, poor consequential thinking, and peer pressure from an older instigator. The Court held the Recorder did not give this sufficient weight.
  • Basis of plea / role: while the incident was correctly treated as a joint attack, the appellant did not inflict the violence and did not use the bat offensively to injure (as accepted by the Crown).

The Court’s reasoning shows how culpability within group offending and maturity-based mitigation interact: even where participation in an armed, premeditated group attack is serious, sentencing must remain calibrated to the individual’s developmental state and actual conduct (especially where violence was principally inflicted by another).

(d) Parity and “disparity” reframed

The appellant advanced disparity by comparing his sentence with Ahmad’s. The Court rejected “disparity” as the correct diagnosis, instead finding a failure to focus on the appellant’s own mitigating features. That reframing is important: parity analysis does not substitute for individualised sentencing; it is an additional check once the correct individual sentence is reached.

(e) Delay

The Court accepted the Recorder had addressed delay appropriately—as supporting suspension and as demonstrating the appellant’s ability to avoid reoffending and gain employment—rather than as a basis for a deeper reduction in the custodial term itself. The judgment therefore treats delay as relevant, but not necessarily transformative, where suspension already reflects its practical effect.

(f) Illegality: imprisonment vs DYOI under section 227 Sentencing Act 2020

Independently of excessiveness, the Court held the sentence was unlawful because it was pronounced as a suspended sentence of imprisonment. The Court stated that “the imposition of a sentence of imprisonment on a person aged under 21 when convicted is prohibited by section 227 of the Sentencing Act 2020.” The correct form is Detention in a Young Offender Institution (DYOI), including where the sentence is suspended.

This part of the decision is a clear procedural and statutory compliance reminder: the custodial “label” is not cosmetic; it is jurisdictionally prescribed by age at conviction.

3.3 Impact

  • Young adult sentencing (18–20): The judgment reinforces that courts must engage with maturity evidence when sentencing those just over 18. It is a practical application of the “no cliff edge” principle and places real weight on PSR maturity assessments.
  • Group violence and individual culpability: Even within a joint enterprise-style factual matrix (a coordinated attack), a sentencing court must still differentiate by role where a basis of plea establishes non-use of a weapon and non-infliction of violence.
  • Guideline discipline: Courts may select a higher category where fear/distress is serious, but must then locate the case properly within the range (here: “lower end” of A1), avoiding near-maximum outcomes where harm is borderline.
  • Sentencing legality for under-21s: The decision is a direct warning that pronouncing “imprisonment” for an offender under 21 at conviction is unlawful; practitioners should check the statutory form (DYOI) at sentence and on drafting of orders.

4. Complex Concepts Simplified

  • Affray: a public order offence involving the use or threat of unlawful violence such that a person of reasonable firmness would fear for their safety.
  • Offensive weapon in a public place: possessing a weapon (or an article intended for causing injury) in public without lawful authority or reasonable excuse.
  • Basis of plea: an agreed factual account upon which the guilty plea is entered and sentence must be based (unless the court resolves a disputed factual issue via a Newton hearing).
  • Manifestly excessive: an appellate standard meaning the sentence is outside the range that a sentencing judge, applying correct principles, could reasonably impose.
  • Double counting: impermissibly punishing the same feature twice (e.g., treating weapon possession as an aggravating factor and also separately punishing it as another offence) without proper totality control.
  • Totality: the principle that the overall sentence for multiple offences must be just and proportionate to the entire offending.
  • Parity: ensuring co-defendants receive broadly comparable sentences when their roles and culpability are similar, while preserving individualised justice where they are not.
  • DYOI (Detention in a Young Offender Institution): the custodial sentence form used for offenders under 21 (as treated in this judgment), distinct from “imprisonment” in terminology and statutory scheme.
  • Suspended sentence order (SSO): a custodial sentence activated only if the offender breaches conditions or commits further offences during the operational period; often paired with requirements such as rehabilitation activity and unpaid work.

5. Conclusion

R v Arshad [2026] EWCA Crim 296 emphasises two connected sentencing imperatives. First, turning 18 is not a sentencing cliff edge: courts must meaningfully assess maturity, especially where PSR evidence shows impulsivity and susceptibility to pressure, and must sentence on the accepted basis of plea and actual role in violence. Second, sentencing courts must ensure statutory legality in the form of custodial sentences: for offenders under 21 at conviction, the correct sentence is DYOI, not “imprisonment”, even when suspended. Together, these strands strengthen principled, individualized, and legally accurate sentencing for young adults involved in serious public disorder and weapon-related offending.