(1)This section applies where—
(a)a person aged 18 or over is convicted of a serious offence committed after the commencement of this section, and
(b)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 him of further specified offences.
(2)If—
(a)the offence is one in respect of which the offender would apart from this section be liable to imprisonment for life, and
(b)the court considers that the seriousness of the offence, or of the offence and one or more offences associated with it, is such as to justify the imposition of a sentence of imprisonment for life,
the court must impose a sentence of imprisonment for life.
(3)In a case not falling within subsection (2), the court must impose a sentence of imprisonment for public protection.
(4)A sentence of imprisonment for public protection is a sentence of imprisonment for an indeterminate period, subject to the provisions of Chapter 2 of Part 2 of the Crime (Sentences) Act 1997 (c. 43) as to the release of prisoners and duration of licences.
(5)An offence the sentence for which is imposed under this section is not to be regarded as an offence the sentence for which is fixed by law.