When does a lenient sentence become unduly lenient?

The unduly lenient sentence (“ULS”) scheme is one of the more unusual features of the criminal justice system. A defendant who has been convicted in the Crown Court of a certain offence can, in prescribed circumstances, find that the handing down of their sentence is not the end of the matter. A sentence which is considered insufficiently severe may be referred by the Attorney General (or Solicitor General) to the Court of Appeal, where it can be increased if the prescribed threshold is met.

The ULS therefore sits uneasily alongside the ordinary finality of sentencing decisions. That tension was brought sharply into focus by the recent decision in R v X, Y and Z, the so-called “Fordingbridge” case.

The case is significant not simply because two teenage defendants who had received Youth Rehabilitation Orders were subsequently sentenced to four years’ detention. Its importance lies in what the Court of Appeal said about the boundary between a sentence which is lenient and one which is unduly lenient.

The underlying offending involved two separate incidents in Fordingbridge, Hampshire, involving two teenage complainants. X and Y, both aged 14 at the time of the offending, participated in both incidents. Z, who was 13, was involved only in the second.

Following a lengthy trial, X and Y received three-year Youth Rehabilitation Orders with intensive supervision. Z received an 18-month Youth Rehabilitation Order. The sentences provoked considerable public criticism and the Attorney General subsequently referred all three sentences to the Court of Appeal under section 36 of the Criminal Justice Act 1988.

The outcome was nuanced. The Court allowed the references in relation to X and Y and imposed four years’ detention on each. It dismissed the reference in respect of Z. His sentence, although the Court considered that his offending crossed the custody threshold, remained a sentence which was properly open to the sentencing judge given his age, limited involvement and particular vulnerabilities.

That distinction is important. The Court was not announcing a new principle that serious offending by children must result in custody. Rather, it concluded that, in the particular circumstances of X and Y, the sentencing judge had materially undervalued both the seriousness of the offending and the harm caused. The decision is therefore better understood as an illustration of the high threshold for ULS intervention being met rather than as a lowering of the bar.

This distinction matters; the ULS scheme is not intended to provide a second opportunity at sentencing simply because the Attorney General, the prosecution, a victim or the public at large considers a defendant has not been adequately punished. The Court of Appeal has repeatedly stressed that sentencing is an evaluative exercise and that legitimate judicial discretion permits a range of outcomes.

The meaning of “unduly lenient” has been comprehensively analysed by the Court of Appeal. The leading authority referred to in Crown Prosecution Service guidance is Attorney General’s Reference No. 4 of 1989, in which Lord Lane sets out that a sentence is unduly lenient “where it falls outside the range of sentences which the judge, applying his mind to all the relevant factors, could reasonably consider appropriate.”

In broad terms, that means that the disputed sentence falls outside the range reasonably available to the sentencing judge, or that there has been a significant error of principle (see Attorney General’s Reference Nos 3 and 5 of 1989).

That high threshold is an important protection for defendants. Without it, the ULS scheme could become an informal prosecution appeal against sentence, undermining the principle that sentencing is primarily a matter for the trial judge.

The statistics demonstrate that the scheme is nevertheless an effective mechanism for correcting serious sentencing errors. In 2022, 819 requests were received by the Attorney General’s Office. Of those, 139 cases were referred to the Court of Appeal and sentences were increased in 95 (approximately 68%). More recently, 48 cases were heard by the Court of Appeal under the scheme between January and March 2025. Thirty-three sentences were increased. Fifteen concerned violent and sexual offences against women and girls.

Those figures should not, however, be interpreted as meaning that 68% of all sentences challenged under the scheme are increased. They concern the much narrower cohort of those which have already survived the Attorney General’s scrutiny and reached the Court of Appeal. Those referred to the Court of Appeal have already been judged by law officers to have merit.

The recent data also reveals a discernible emphasis on serious sexual and violent offending. In the first half of 2025, 62% of sentences increased by the Court of Appeal under the ULS were for rape and serious sexual offences – up from 41% in the first half of 2024 and 30% in the first half of 2023. Twenty-eight offenders convicted of violent or sexual offences against women and girls had their sentences increased during the first six months of 2025.

In July 2026, Robert Richens had his minimum term increased by more than three years for the murder of his former partner, with the Court of Appeal finding that the sentencing judge had failed to increase the sentence sufficiently in light of the many aggravating factors, and had allowed too great a reduction for the defendant’s learning disabilities in circumstances where it had not been established that they had operated to reduce his culpability.

The scheme has also been used in cases of controlling and coercive behaviour. In R v Humphreys, a suspended sentence was quashed and replaced with two years and four months’ imprisonment following an Attorney General reference. The offending included controlling behaviour, financial abuse, threats and violence towards the defendant’s partner.

The most significant aspect of the Fordingbridge case is perhaps the Court’s insistence upon disciplined sentencing analysis. This is particularly important in cases which provoke public outrage, and is a timely reminder that a referral under the ULS scheme should not create the expectation of an increased sentence.

For X and Y, the Court considered that the sentencing judge had failed properly to account for the fact that the offending involved two separate incidents, two separate victims and repeated sexual offending, accompanied by filming and humiliation. The Court considered that the harm suffered by the complainants had also been materially underestimated. But the judgment is equally significant for what it did not do.

It did not dispense with the principle that custody for children is a last resort. It did not equate youth sentencing with adult sentencing, and it did not say that crossing the custody threshold automatically requires imprisonment.

Indeed, Z’s case demonstrates the opposite. The Court accepted that the custody threshold had been crossed but nevertheless concluded that a non-custodial sentence remained properly available to the sentencing judge. The existence of a ULS reference does not mean that the Court of Appeal starts from the proposition that the original sentence was wrong. It must still conduct the statutory and guideline analysis carefully and decide whether the sentence was unduly lenient, in a similar way to the analysis of a defendant’s appeal against sentence, where the question for the court is whether a sentence is “manifestly excessive.”

A useful counterpoint to the Fordingbridge case is that of R v Long, Bowers and Cole. This was a reference by the Attorney General concerning the sentences imposed on the three defendants convicted of the manslaughter of PC Andrew Harper in 2019. The Court of Appeal in that case, in the face of widespread outcry, declined to find that the sentences of 16 years (for Henry Long) and 13 years each for Albert Bowers and Jessie Cole were unduly lenient.

That case has once again been thrust into the spotlight in the context of the Government’s early release scheme. Whilst the Court of Appeal maintained the original sentences, the new Government under Andy Burnham has had to introduce carve-outs to that scheme in order to ensure that the trio serve at least the standard two-thirds of their sentences before becoming eligible for release. In announcing these additional exceptions to the scheme, the Prime Minister directly referenced the PC Harper case. This politically expedient adherence to public pressure demonstrates aptly why it is so important that the Court of Appeal is able to maintain consistency and objectivity in dealing with statutory references under the ULS scheme. Equally, it highlights why the role of the Attorney General’s Office in filtering requests for referrals should be protected, in circumstances where the number of requests is likely to increase over the coming months and years. The Victims and Courts Act 2026, which was passed on 29 April 2026, increases the time limit for requesting a review from 28 days to six months, giving a far greater number of victims, families and interested observers time to formulate their applications. From a defence perspective, it is notable that the equivalent time limit in place for a defendant to submit an appeal against a sentence believed to be manifestly excessive remains at 28 days.

There is an obvious temptation, particularly for those impacted directly by criminal offending, to regard the ULS scheme as a mechanism for correcting sentences which appear unjustifiably low, or which do not do justice to the harm caused to victims or their families. However, that is not its legal function, and the Fordingbridge case demonstrates the distinction particularly well. The public controversy surrounding the sentences was intense, but the Court of Appeal’s decision ultimately rested upon detailed analysis of the applicable sentencing principles, the seriousness of the offending, the assessment of harm and the individual circumstances of each defendant.