SACRAMENTO, Calif. >> The lawyer for Sirhan Sirhan, who assassinated presidential candidate Robert F. Kennedy in 1968, on Wednesday asked a judge to free him and played a recording of her client saying he is now dedicated to nonviolence and wants only to “return home to my brother and live the rest of our days in peace.”

Sirhan, 78, has spent 54 years in prison. In a 3 1/2-minute message played during a news conference held by his lawyer, he said he feels remorse every day for his actions.

“To transform this weight into something positive, I have dedicated my life to self-improvement, the mentoring of others in prison on how to live a peaceful life that revolves around nonviolence,” he said. “By doing this, I ensure that no other person is victimized by my actions again and hopefully make an impact on others to follow.”

It was the first time Sirhan’s voice had been heard publicly since a televised parole hearing in 2011, before California barred audio or visual recordings of such proceedings.

Sirhan shot Kennedy moments after the U.S. senator from New York claimed victory in California’s pivotal Democratic presidential primary. He wounded five others during the shooting at the Ambassador Hotel in Los Angeles.

Sirhan originally was sentenced to death, but that sentence was commuted to life when the California Supreme Court briefly outlawed capital punishment in 1972.

He was denied parole 15 times until last year, when a board recommended his release. But California Gov. Gavin Newsom rejected his freedom in January, saying that Sirhan remains a threat to the public and hasn’t taken responsibility for a crime that changed American history.

Sirhan’s attorney, Angela Berry, filed a petition Wednesday asking a Los Angeles County Superior Court judge to reverse Newsom’s denial. She said there is no evidence that Sirhan remains dangerous.

Sirhan’s younger brother, Munir Sirhan, has said his brother can live with him in Pasadena, California, if he is paroled. Sirhan Sirhan has waived his right to fight deportation to his native Jordan.

Berry filed a 53-page writ of habeas corpus asking the judge to rule that Newsom violated state law, which holds that inmates should be paroled unless they pose a current unreasonable public safety risk. Recent California laws also required the parole panel to consider that Sirhan committed the offense at a young age — 24 — and that he is now an elderly prisoner.

She is challenging the governor’s reversal as an “abuse of discretion,” a denial of Sirhan’s constitutional right to due process and as a violation of California law. She also alleges that Newsom misstated the facts in his decision.

Berry said the governor “acted with personal bias, incorporated the wrong law, ignored mitigation evidence, and did not afford Sirhan the same rights as others eligible for parole.”

The governor has cited RFK as his political hero and keeps RFK photos in both his official and home offices, including one of Kennedy with his late father. Berry accused him of politicizing the parole process.

Newsom’s office declined to comment.

Newsom overruled two parole commissioners who had found that Sirhan no longer was a risk. Among other factors, Newsom said the Christian Palestinian who immigrated from Jordan has failed to disclaim violence committed in his name, adding to the risk that he could incite political unrest.

The ruling split the Kennedy family, with RFK’s wife, Ethel Kennedy, and six of Kennedy’s nine surviving children opposing his parole.

“The political passions that motivated this inmate’s act still simmer today, and his refusal to admit the truth makes it impossible to conclude that he has overcome the evil that boiled over 53 years ago,” they wrote when Newsom rejected his parole.

They did not immediately respond to a request for comment on Wednesday’s court filing.

In his recording, Sirhan noted that one of his wounded victims, Paul Schrade, and two of Kennedy’s sons — Douglas Kennedy and Robert F. Kennedy Jr. — supported his release.

“I’m humbled by their love and empathy as it very rare that an offender’s victims stand with them to support their freedom,” Sirhan said in a steady, unemotional voice during the recorded call made earlier this week from the Richard J. Donovan Correctional Facility in San Diego.

Jen Abreu, executive director of the rehabilitation program provider group Redemption Row California, said during the news conference that she helped coach Sirhan for 18 months before his parole hearing, helping him win a positive recommendation after so many denials.

“He needed help in being able to demonstrate these positive attributes,” Abreu said. “Sirhan has set a benchmark in prison-based rehabilitation” with no disciplinary reports in 49 years, she said. “To have an immaculate record for almost five decades is the exception, not the rule.”

Berry said the court process will take several months at a minimum, and either side could appeal. Sirhan is set for a new parole hearing on March 1 and she said the two could overlap and proceed simultaneously.