SAN FRANCISCO — California Gov. Gavin Newsom plans to announce Wednesday an executive order that immediately establishes a moratorium on killing convicts on death row, USA TODAY learned Tuesday night.

California has 737 people on death row, about a quarter of the nation’s death row population and by far the most of any state. Some 24 of them have been convicted of murder and have exhausted their appeals, meaning they could be scheduled to die under Newsom’s governorship.

“The intentional killing of another person is wrong,” Newsom, 51, is slated to say during the signing of the executive order. “And as governor, I will not oversee the execution of any individual.”

The order grants an immediate reprieve for all individuals sentenced to death in the state. It draws its power from a governor’s ability to commute death sentences. Typically, such commutations are done individually, but in this case the state’s chief executive is establishing a blanket moratorium.

Governors in Oregon, Colorado and Pennsylvania have established similar moratoriums leveraging the same executive powers.

Newsom's policy change come as support for the death penalty has declined over the decades. According to a Pew Research Center survey conducted last year, 54 percent of Americans are in favor of capital punishment for murder while 39 percent are opposed. That's down significantly from 1996, when 78 percent supported it.

In 2016, California voters narrowly rejected Proposition 62, which would have turned all death sentences into life without the possibility of parole.

Newsom has long been vocal about his opposition to the death penalty, tweeting on Election Day in 2016 that “the death penalty is a failed policy that wastes money & is fundamentally immoral.”

Talking points issued by Newsom’s office Tuesday noted a variety of reasons for the governor’s moratorium, including his position that the death penalty is inherently racist and biased against the mentally ill; the wrongfully convicted sometimes die at the hands of the state; and capital punishment is costly and does not increase safety.

"In America, we execute more human beings than any other democracy on earth," Newsom is scheduled to say. "Just in 2017, the United States joined Iran, Iraq, Saudi Arabia, Somalia, Pakistan, China and Egypt as the world’s top executioners."

Newsom will add that the death penalty "has provided no public safety benefit or value as a deterrent. It has wasted billions of taxpayer dollars. But most of all, the death penalty is absolute. Irreversible and irreparable in the event of human error."

California has not killed an inmate since 2006 at San Quentin State Prison, the site of many anti-death penalty vigils over the decades, in large part because of sustained legal challenges that have held up such executions.

Such legal challenges from groups including the American Civil Liberties Union are not likely to go away. But Newsom’s executive order makes it less likely that the two dozen inmates who have run out of appeals will see the gas chamber.

The number of death row executions in the U.S. peaked in 1998 at 98, according to the Pew study. Since then it has fallen greatly, with 23 inmates executed in 2017. Eight states — Alabama, Arkansas, Florida, Georgia, Missouri, Ohio, Texas and Virginia — accounted for all executions in 2017, compared with 20 states in 1999.

Newsom's moratorium affects prisoners on death row, but there's evidence the pipeline is shrinking since the state's death penalty cases are declining, according to a report by Safe California, a site focusing on death penalty initiatives. In a 2018 survey of cases by county, Los Angeles reported two death sentences (down from 14 in 2017), Orange County one death sentence (down from six) and Kern County had zero (down from four).

A growing number of Democratic leaders, including presidential candidates Sen. Kamala Harris of California and Sen. Bernie Sanders of Vermont, support abolishing the death penalty, while President Donald Trump has said he supports capital punishment for drug dealers and anyone who murders a police officer.

Pope Francis weighed in on the topic in August 2018, saying, “the death penalty is inadmissible because it is an attack on the inviolability and dignity of the person." He said the Catholic Church should work toward its abolition worldwide.

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