An extended sentence of detention in a young offender institution is a sentence of detention in a young offender institution the term of which is equal to the aggregate of—
(a)the appropriate custodial term (see section 268), and
(b)a further period (the “extension period”) for which the offender is to be subject to a licence.
(1)An extended sentence of detention in a young offender institution is available in respect of an offence where—
(a)the offence is a specified offence (see section 306(1)),
(b)the offender is aged at least 18 but under 21 when convicted of the offence,
(c)the court is of the opinion that there is a significant risk to members of the public of serious harm occasioned by the commission by the offender of further specified offences (see section 308),
(d)the court is not required by section 273 or 274 to impose a sentence of custody for life, and
(e)the earlier offence condition or the 4 year term condition is met.
(2)The pre-sentence report requirements (see section 30) apply to the court in relation to forming the opinion mentioned in subsection (1)(c).
(3)The earlier offence condition is that, when the offence was committed, the offender had been convicted of an offence listed in Schedule 14.
(4)The 4 year term condition is that, if the court were to impose an extended sentence, the term that it would specify as the appropriate custodial term (see section 268) would be at least 4 years.
(1)This section applies where a court dealing with an offender for an offence imposes, or is considering whether to impose, an extended sentence of detention in a young offender institution under section 266.
(2)The appropriate custodial term is the term of detention in a young offender institution that would be imposed in respect of the offence in compliance with section 231(2) (length of discretionary custodial sentences: general provision) if the court did not impose an extended sentence.
(3)The extension period must be a period of such length as the court considers necessary for the purpose of protecting members of the public from serious harm occasioned by the commission by the offender of further specified offences.
This is subject to subsections (4) and (5).
(4)The extension period must—
(a)be at least 1 year, and
(b)not exceed—
(i)5 years in the case of a specified violent offence, or
(ii)8 years in the case of a specified sexual offence or a specified terrorism offence.
See section 306(2) for the meanings of “specified violent offence”, “specified sexual offence” and “specified terrorism offence”.
(5)The term of the extended sentence must not exceed the maximum term of imprisonment with which the offence is punishable in the case of a person aged 21 or over.