Otherwise they can be returned to confinement to complete their sentence. Beginning in 1992, all English inmates, regardless of sentence length, were required to serve a minimum of one-half of their sentence. Once they serve half, those with sentences under four years are automatically released and those with sentences of four years or more become eligible for parole. Parole regulations in the United States vary from State to State, between Federal and State parole, between State and local jurisdictions and over time. Consequently, they cannot be simply described.
Most States have parole boards with jurisdiction over persons with sentences of a year or more.
Time served is greater in the United States than in England, mostly because courts impose longer sentences in the United States than in England.