Under an IPP, offenders convicted of a wide range of offences are given a minimum tariff.

BBC: Indefinite jail sentences 'harm' inmates

Christopher Halliwell, 48, was jailed in October for life with a minimum tariff of 25 years for the murder of Sian O'Callaghan, 22, from Swindon.

BBC: Christopher Halliwell murder tariff to stand

Remanding Cavan into custody, the judge adjourned fixing the minimum tariff until pre-sentence probation reports, psychiatric reports and a victim impact statement have been compiled.

BBC: The apartment block where a man's body was found

Barton, whose brother is Manchester City footballer Joey Barton, and Taylor face a mandatory life sentence and the minimum tariff for racially motivated murders is 30 years.

BBC: Barton and Taylor followed Anthony to McGoldrick Park

During his departmental question session on 10 November, he told MPs that he had carried out a review following "considerable concern" about the 15-year starting point for judges considering the minimum tariff in knife murders.

BBC: Justice questions

He has passed his minimum 20 year tariff but the Parole Board has refused to release him on licence from Wakefield Prison.

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At the Appeal Court in London King's lawyers argued the tariff - the minimum term he must serve - was too long given his youth at the time.

BBC: Bleddyn King