19. Circumstances in which an extended sentence of imprisonment may be imposed.

The court1 may impose an extended sentence of imprisonment where2:

  1.  

    (1)     a person aged 18 or over3 is convicted of a specified offence (whatever the date on which the offence was committed)4;

  2.  

    (2)     the court considers that there is a significant risk to members of the public of serious harm5 occasioned by the commission by the offender of further specified offences6;

  3.  

    (3)     the court is not required7 to impose a sentence of imprisonment for life