What is the form of conditional release granted after a prisoner has served part of his sentence?

The correct choice is parole, which refers to the conditional release of a prisoner before the completion of their full sentence. This means that the individual has served a portion of their sentence and is allowed to reintegrate into society under specific conditions. These conditions may include regular check-ins with a parole officer, restrictions on movement, or participation in rehabilitation programs.

Parole aims to assist the individual in transitioning back into the community while still maintaining some level of supervision to reduce the risk of reoffending. It is distinct from other forms of release, as it often occurs after a portion of a sentence has been served rather than at the beginning.

In contrast, a conditional pardon typically involves the complete forgiveness of a crime but may still require certain conditions to be met. Probation is an alternative to incarceration rather than a release from prison, and commutation refers to the reduction of a sentence length rather than a supervised release. Understanding the nuances of these terms is important for grasping the various avenues available in the correctional system.