Legal background Sentencing and release: Scotland Indeterminate sentences
These are sentences that do not have a set end point, such as a life sentence. The court will set a "punishment part" for such sentences which is the minimum time an offender must spend in prison. 'Discretionary’ life is the statutory term introduced under the 1993 Act to distinguish prisoners sentenced by the court to life from those whose life sentence for murder is mandatory, being fixed by law.
	A mandatory life sentence must be given for murder whereas a discretionary life sentence can be given for other extremely serious offences at the discretion of the court. For both these types of life sentence, the court sets the minimum custodial punishment time. After that minimum time, offenders will remain in prison unless the Parole Board for Scotland decides that they are safe to be released into the community under lifelong conditions.