The term is used to describe detention in prison for an indefinite length of time;[REF] a judge may rule that a person be "detained at Her Majesty's pleasure" for serious offences or based on a successful insanity defence [REF].
Prisoners held at Her Majesty's pleasure are frequently reviewed to determine whether their sentence can be deemed complete; although this power traditionally rested with the monarch, such reviews are now made by others-the Home Secretary in Britain, for instance.