(1)This section applies to a short-term or long-term prisoner sentenced to a term of imprisonment (in this section referred to as “the original sentence”) by a court in Scotland and released under this Part of this Act or Part II of the [1991 c. 53.] Criminal Justice Act 1991 if—
(a)before the date on which he would (but for his release) have served his sentence in full, he commits an offence punishable with imprisonment (other than an offence in respect of which imprisonment for life is mandatory); and
(b)whether before or after that date, he pleads guilty to or is found guilty of that offence (in this section referred to as “the new offence”) in a court in Scotland or England and Wales.
(2)Where the court mentioned in subsection (1)(b) above is in Scotland it may, instead of or in addition to making any other order in respect of the plea or finding—
(a)in a case other than that mentioned in paragraph (b) below, order the person to be returned to prison for the whole or any part of the period which—
(i)begins with the date of the order for his return; and
(ii)is equal in length to the period between the date on which the new offence was committed and the date mentioned in subsection (1)(a) above; and
(b)in a case where that court is inferior to the court which imposed the sentence mentioned in the said subsection (1)(a), refer the case to the superior court in question; and a court to which a case is so referred may make such order with regard to it as is mentioned in paragraph (a) above.
(3)Where the court mentioned in subsection (1)(b) above is in England and Wales it may, instead of or in addition to making any other order in respect of the plea or finding, refer the case to the court which imposed the original sentence and shall, if it does so, send to that court such particulars of that case as may be relevant.
(4)The court to which a case is referred under subsection (3) above may make such an order as is mentioned in subsection (2)(a) above in respect of the person.
(5)The period for which a person to whom this section applies is ordered under subsection (2) or (4) above to be returned to prison—
(a)shall be taken to be a sentence of imprisonment for the purposes of this Act and of any appeal; and
(b)shall, as the court making that order may direct, either be served before and be followed by, or be served concurrently with, any sentence of imprisonment imposed for the new offence (being in either case disregarded in determining the appropriate length of that sentence).
(6)In exercising its powers under section 254(3) or 453C(1) of the 1975 Act, the court hearing an appeal against an order under subsection (2) or (4) above may, if it thinks fit and notwithstanding subsection (2)(a), substitute for the period specified in the order a period not exceeding the period between the date on which the person was released and the date mentioned in subsection (1)(a) above.
(7)Where an order under subsection (2) or (4) above is made in respect of a person released on licence and he is sentenced in respect of the new offence to a term of imprisonment of less than four years, section 1(1) of this Act shall apply in respect of that sentence as if for the word “unconditionally” there were substituted the words “on licence”.