SAN DIEGO?The San Diego County district attorney's office said Wednesday it filed a lawsuit that seeks to nullify Arnold Schwarzenegger's commutation of a prison sentence for a political ally's son shortly before his term as California governor ended in January.

District Attorney Bonnie Dumanis told reporters the lawsuit filed by her office on behalf of the victims is believed to be the first of its kind in the nation.

The civil lawsuit filed in San Diego County Superior Court is the latest fallout from the Republican governor's decision, which angered prosecutors, the victim's family and other Republicans.

A day before his gubernatorial term ended, Schwarzenegger reduced from 16 years to seven years the sentence given to Esteban Nunez, son of former California Assembly Speaker Fabian Nunez.

The younger Nunez had pleaded guilty in the 2008 stabbing death of a San Diego college student, 22-year-old Luis Santos.

In the lawsuit, Dumanis alleges Schwarzenegger violated the rights of victims and their families because he did not notify them or the district attorney's office and allow them to have input before commuting the sentence as required under California's Marsy's Law.

Dumanis made clear that her office is not challenging the power of governors to grant pardons or commutations that is meant to insure against miscarriages of justice.

"Instead, this last-minute commutation made without all the facts or input from the parties only fueled the public's mistrust of government and greatly diminished justice," she said.

The lawsuit seeks to reinstate the 16-year sentence. It names current Gov. Jerry Brown, the director of the state Department of Corrections, a state prison warden and Esteban Nunez and asks the court to issue an order preventing them from allowing Esteban Nunez from being released under the reduced sentence.