Murder (Abolition of Death Penalty) Act 1965 all sentences of death were to be commuted to sentences of life imprisonment. The legislation contained a sunset clause, which stated that the Act would expire on 31 July 1970 "unless Parliament by affirmative resolutions of both Houses otherwise determines". This was done in 1969 and the Act was made permanent. The Act left four capital offences: high treason, "piracy with violence" (piracy with intent to kill or cause grievous bodily harm), arson in royal dockyards and espionage, as well as other capital offences under military law. The death penalty was not finally abolished in the United Kingdom until 1998
High treason in the United Kingdom sentence of life imprisonment instead of death (but today, due to the abolition of the death penalty, the maximum penalty both for high treason and treason felony would be the same—life imprisonment). Under the traditional categorisation of offences into treason, felonies, and misdemeanours, treason felony was merely another form of felony. Several categories of treason which had been introduced by the Sedition Act 1661 were reduced to felonies. While the common law offences of misprision and compounding were abolished in respect of felonies (including treason felony) by the Criminal Law Act 1967, which abolished the distinction between misdemeanour and felony,