MA H1977

Creates new "accomplice murder" offense for individuals who aid in a killing but are not the principal perpetrator, with sentencing of 2.5 to 25 years in state prison instead of standard murder penalties

Allows persons convicted of murder under joint venture theory to petition for resentencing, with prosecutors required to notify eligible incarcerated individuals within 90 days of the law's passage

Places burden on prosecution to prove beyond a reasonable doubt that petitioner is ineligible for resentencing; if prosecution fails, conviction is vacated and petitioner is resentenced on remaining charges

Applies retroactively to anyone charged or convicted of aiding in a killing prior to, on, or after the effective date of the act

Requires Attorney General to report annually to the judiciary committee on petitions filed, resentencing outcomes, and demographic data including race, ethnicity, and gender of petitioners