Dangerous offender

In Canada and England and Wales, certain convicted persons may be designated as dangerous offenders and subject to a longer, or indefinite, term of preventive detention in order to protect the public.

In Canadian criminal law, a convicted person who is designated a dangerous offender may be subjected to an indeterminate prison sentence, whether or not the crime carries a life sentence, but this does not apply to convictions of first degree murder, second degree murder, high treason, and treason. The purpose of the legislation is to detain offenders who are deemed too dangerous to be released into society because of their violent tendencies, but whose sentences would not necessarily keep them incarcerated under other legislation, such as the Correctional and Conditional Release Act. Under subsection 761(1) of the Criminal Code, the Parole Board of Canada is required to review the case of an offender with a dangerous offender label after seven years, and parole may be granted as circumstances warrant, but the offender would remain under supervision indefinitely. After the initial review, the Parole Board must conduct subsequent reviews every two years. According to Corrections Canada, on average 24 dangerous offenders are admitted to the Canadian prison system each year. Paul Bernardo is one well-known dangerous offender.

The dangerous offender provisions have been found constitutional: "The individual, on a finding of guilty, is being sentenced for the 'serious personal injury offence' for which he was convicted, albeit in a different way than would ordinarily be done. He is not being punished for what he might do. The punishment flows from the actual commission of a specific offence."

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