Relating to sentencing mitigation; prescribing an effective date; providing for criminal sentence reduction that requires approval by a two-thirds majority.

Requires sentencing court to consider as mitigation evidence defendant was subjected to domestic abuse that was significant factor in criminal behavior. Provides that such evidence constitutes substantial and compelling reasons justifying downward departure sentence. Authorizes court to impose lesser sentence even if sentence is mandatory or otherwise required by law. Creates procedure by which person currently serving sentence may petition court for resentencing if person was subjected to abuse that was significant factor in criminal behavior. Takes effect on 91st day following adjournment sine die.