Turning 18

Published June 2020
Partially updated March 2021

The law considers those who turn 18 between the commission of an offence and the start of criminal proceedings to be adults. Even if they were technically adults at the time of the offence, it is increasingly recognised that young people do not gain full maturity on their 18th birthdays.  The challenge practitioners face is to ensure that there is as much recognition as possible of the young person’s age at the time they offended, and their age and maturity at each significant stage of a case.

In this guide you will find help in navigating through the different regimes, rules and principles.

A decision to divert

For offences committed as a child

For a child suspect, there is what is commonly regarded as a ‘presumption’ in favour of diverting from prosecution by offering an Out of Court Disposal (OOCD).

The emphasis on diversion is the product of recognition that diverting children from prosecution is more likely to prevent offending. Criminalising children should be avoided due to the likely detrimental impact. 

As a result, a number of informal and formal OOCDs are routinely made available for children as an alternative to prosecution. Informal OOCDs, such as Triage, can involve informal engagement with the Youth Offending Team (YOT). Formal diversion refers to youth cautions and youth conditional cautions. When a person engages with an informal OOCD the police record the outcome as No Further Action (NFA). This is not automatically disclosed on a standard or enhanced Criminal Record Certificate.

For a suspect who has offended as a child, having turned 18 when the decision to divert is made has particular consequences:

• the suspect will no longer be eligible for any of the youth informal or formal OOCDs.
• Ministry of Justice and Youth Justice Board guidance stipulates that an adult simple caution should be offered, if the suspect is eligible for one. 

For offences committed as an adult

For a suspect who is a young adult when they offend, having turned 18 has the following consequences.

• The circumstances in which an adult may be offered a caution (simple  or conditional ) are limited.
• For serious offending, that otherwise may have been addressed by a formal youth OOCD, the exceptional circumstances provisions must apply for a caution to be offered. 

The exceptional circumstances provisions make it possible for an adult suspect to be offered a caution when, due to the seriousness of the offence, this disposal ordinarily would not be available. Under these provisions, the police are entitled to consider mitigating factors such as:

• a defendant’s age at time of their offending;
• their level of maturity; and
• the impact of these issues on culpability and likely sentence (see “Sentencing for offences committed as a young adult” on page 10). 

A decision to charge

For offences committed as a child

A suspect who has turned 18 at the time a decision to charge is made will be regarded as an adult in the eyes of the law.

However, the public interest considerations of the Full Code Test require the reviewing lawyer to consider the suspect’s age and maturity at the time of the offence in any decision to prosecute. 

Guidance exists for various disposals such as OOCDs and sentence, and is referred to throughout this guide. The guidance suggests that young adults being dealt with after turning 18 should be dealt with similarly to how they would have been if still a child.

For offences committed as an adult

The public interest considerations of the Full Code Test require prosecutors to consider:

‘…the suspect’s maturity, as well as their chronological age, as young adults will continue to mature into their mid-twenties. As a starting point, the younger the suspect, the less likely it is that a prosecution is required.’ 

Prosecutors are:

• under a continuing duty to review the public interest in a prosecution,  and
• have the power to refer the case to the police for a caution/conditional caution, even after a defendant has been charged. 

*Please note that the footnotes in this table are visible in the table image and do not appear in the footnotes at the end of the document.

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For offences committed as a child

• If a defendant is 17 when proceedings start but turns 18 before the conclusion of proceedings the youth court can continue to deal with the case or send the case to be heard in the adult magistrates’ court. 
• The relevant date for ‘start of proceedings’ is the date of the hearing at which the mode of trial and plea  is considered. Or, if no mode of trial hearing takes place, when the charge is put. 

*Please note that the footnote in this graphic is visible in the image and does not appear in the footnotes at the end of the document.

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Turning 18 before bail and remand decision

• Turning 18 before any decision is made as to bail and remand will result in a young adult losing the benefit of the careful guidance governing bail for child defendants. The guidance is that all parties should maximise the availability of bail and treat custody as the measure of last resort.
• The court may be less likely to grant bail for serious or repeat offending. This is due to the absence of YOT supervised bail conditions and the impact of this on the court’s assessment of the risk of reoffending and risk to the public.

Turning 18 during proceedings

• The YOT may continue to supervise bail if a defendant is on conditional bail. 
• If a defendant turns 18 while on remand in the youth custodial estate they can be transferred to the adult estate. Where possible this should be avoided. 
• Transition planning must take place as the child reaches 18 years of age. The type of custodial sentence expected is a factor affecting the decision on whether a transfer to the adult custodial estate is suitable. 

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Sentencing powers

The general rule is that sentencing powers are determined by a defendant’s age at the date of conviction. 

Turning 18 before proceedings start

• Only adult disposals will be available to the court, despite the defendant being sentenced for offences committed as a child.
• Sentence must be conducted in accordance
  with the principles established in R v Ahmed
  and Ors.  
• The court must have regard to the maximum
  sentence that would have been available at the
  time of the defendant’s offending and, as its
  starting point, the court should take the sentence
  which would have been imposed if the
  defendant had been sentenced as a child. 

Turning 18 during proceedings and before conviction

Despite the general rule, the youth court may retain the sentence of a child who turns 18 before conviction if crossing the age threshold occurs during the proceedings. Alternatively, the court may exercise a discretionary power to remit sentence to the adult magistrates’ court. 

Where a sentence is retained, the youth court may give a youth sentence.  This means that a defendant may receive a Referral Order, Youth Rehabilitation Order or Detention and Training Order, despite the defendant turning 18 before conviction.  However, this will often be met with resistance from the YOT, for whom supervision of the order will be complicated. Practitioners aiming for this outcome will need to liaise closely with the YOT and are likely to need to persuade them that exceptional circumstances apply.

Where a case is remitted to the adult magistrates’ court, the following rules apply:

• There is no right of appeal against a decision to remit. 
• The youth court may rescind the remittal at any stage before sentence. 
• The youth court may not remit sentence for an indictable only offence. 
• The adult magistrates court may deal with the defendant in any way they would have dealt with an adult offender,  and
• as a result may theoretically commit to the Crown Court for sentence. In R v Denny  the Court of Appeal held that the court’s remittal of an 18 year old who was convicted of robbery in the youth was unlawful, because the adult magistrates’ court does not have the jurisdiction to deal with an adult indictable only offence. This may be a factor weighing against the exercise of the power.

Turning 18 between conviction and sentence

A defendant who turns 18 after conviction and before sentence will receive a youth sentence.

Sentencing principles

The approach to sentence for a young person who has turned 18 between offence and conviction is set out in R v Imran Ghafoor. 

This approach has been considered in subsequent cases and is supplemented by guidance in the Definitive Guideline for the Sentencing of Children and Young People:

1. The starting point is the sentence that would have been passed at the date of the commission of the offence. 

• Culpability should be judged considering the young adult defendant’s age at the time of the offence. 

2. It will rarely be appropriate for the court to impose a more severe sentence than the maximum that the court could have imposed at the time the offence was committed. 

• A sentence at or close to the maximum may be appropriate.
• A retrospective increase in sentence because of the crossing of the age threshold should be avoided. 

3. The starting point principle is a powerful factor  and there must be a good reason to depart from it, however it is not an inflexible rule. 

• Length of the gap between offending and conviction: where there is a short gap it will rarely be appropriate to impose a longer sentence. 
• Whether there has been a significant change in circumstances.
• Reason for crossing the age threshold: defendant’s fault  or delay in prosecution. 

4. The Definitive Guideline for the Sentencing of Children and Young People continues to be relevant to sentence. 

• Sentencing should be conducted in accordance with the principal aim of the youth justice system (to prevent offending by children and young people) and considering the child or young person’s welfare.
• The sentencing exercise or sentence passed should be individualistic, offender focussed, and place an emphasis on rehabilitation and reintegration.
• Culpability should be carefully considered, as children are not fully developed and they have not attained full maturity.
• Important factors in assessing culpability include the defendant’s emotional and developmental age, in addition to the defendant’s chronological age.
• In most cases offending is a phase that passes fairly quickly and should be regarded as such.
• The effect of any punishment should be considered carefully, as it may be felt more heavily by a child in comparison with an adult.
• Custody is the measure of last resort.

5. The statutory objectives of adult sentencing are relevant. 

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The mitigation afforded by youth and immaturity may justify a young adult being treated differently at sentence. This would come primarily, even with serious offending, through a reduction in the sentence. 

Furthermore, at sentence, the factors relevant to the sentencing of children may also apply.  The aim of rehabilitation also continues to be an important factor. 

Principles

Issues of youth, developmental age, and immaturity are now recognised as factors that may: 

1. diminish a young adult’s culpability; and
2. effect how people young respond to sentence.

In the leading case of Clarke,  the Court of Appeal recognised that:

'Reaching the age of 18 has many legal consequences, but it does not present a cliff edge for the purposes of sentencing. So much has long been clear. The discussion in R v Peters  is an example of its application. Full maturity and all the attributes of adulthood are not magically conferred on young people on their 18th birthdays. The youth and maturity of an offender will be factors that inform any sentencing decision, even if an offender has passed his or her 18th birthday.’ 

Clarke has been considered in subsequent cases. In R v Balogun  the court held that the factors relevant to sentencing a child do not cease to have relevance just because the offender was 18 when they offended. In R v Daniels  the court held that factors in the guideline for sentencing children can have weight when considering the appropriate sentence in cases involving young adults who are not fully mature.

Sentencing guidelines: age and maturity

In 2019 the Sentencing Council issued new guidance for ‘Age and/or Lack of Maturity’ as a mitigating factor. This appears online within the Sentencing Council’s ‘General Guideline: Overarching Principles’ guidance and can be found in a drop down box when this mitigating factor is selected by the user. In summary, the guidance draws on the reasoning of the decision in Clarke and sets out the following principles:

• Age and/or lack of maturity can affect the young person’s responsibility for the offence and the effect of sentence on the young person. Either or both of these considerations may justify a reduction in the sentence.
• Emotional and developmental age is of at least equal importance to a defendant’s chronological age (if not greater).

Young adults are still developing neurologically and consequently may be less able to: evaluate the consequences of their actions; and limit impulsivity and limit risk-taking, particularly when exposed to peer pressure, to which they are more likely to be susceptible.

A young person’s environment, including factors such as adverse childhood experiences, abuse and deprivation, may affect their neurological development.

Immature offenders may find it particularly difficult to cope with custody and the requirements of a community order without appropriate support.

Immature offenders have a greater capacity for change, are more responsive to rehabilitation, and either stop committing crime, or begin a process of stopping, in their late teens and early twenties.

When considering a custodial or community sentence for a young adult the National Probation Service should address these issues in a PSR.

Establishing immaturity

The key principle to have emerged from Court of Appeal decisions following Clarke  is that age alone may be insufficient a factor from which to infer immaturity.

Factors which have been treated as illustrative of a young adult’s immaturity include:

• short-lived episodes of offending, including repeat offending 
• the trajectory of a young adult’s decline into criminal behaviour,  even where the offending is serious 
• environmental factors such as abuse in childhood 

Factors which have been treated as illustrative of a young adult’s maturity include:

• offending that could be described as sophisticated  and/or serious,  including serious offending by a defendant who has experienced childhood trauma  
• repeat offending over an extended period of time, where it could be described as serious  
• a young adult’s intelligence and educational background 

Evidence that may support a finding of immaturity includes:

• the opinion of a PSR author 
• the opinion of an expert such as a psychologist

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Referral Orders and Youth Rehabilitation Orders

Supervision of the order

The YOT has the power to either retain supervision of a young adult or transfer to adult services, that is, the Probation Service. Transition will be conducted in accordance with transition guidance, taking into account a young adult’s circumstances. 

Breach

If a young adult is 18 by the date of a first appearance for any breach proceedings, the case will be dealt with in the adult magistrates’ court. If the Youth Rehabilitation Order (YRO) is revoked and the young adult resentenced, the court’s sentencing powers are limited to those available at the date of conviction for the original offence. 

Detention and Training Order (DTO)

A young adult who turns 18 at the half-way point of a DTO shorter than 24 months will be subject to an extended period of supervision. 

Where a defendant breaches a DTO by failing to comply with their supervision requirements, breach proceedings must be dealt with in the youth court.  If the breach is proved the court has the following options:

• to impose a further period of custody 
• to impose a further period of supervision 
• to impose a fine 
• no action 

If a further period of custody or supervision is imposed, the extended period will be either up to three months or the length of time from the date the breach was committed until the end of the order, whichever is shorter. 

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