Gavin Newsom has the chance to make history.

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On Jan. 17, 2006, California carried out what would turn out to be the last execution in the Golden State in the next two decades. Clarence Ray Allen was put to death at San Quentin State Prison, having been convicted of three counts of first-degree murder with special circumstances for a crime committed in 1980.

At the time of his crimes, the murder rate in California was at or near an all-time high. There were approximately 14.5 homicides per 100,000 people in the state.

Like many places, California had been in the grip of a suffocating and punitive tough-on-crime politics.

Things are different today. California has learned to live without executions, and it is better off because of it.

Its governor, Gavin Newsom, made his state’s execution pause official when he declared a formal moratorium in 2019. He has led the way in asking citizens of his state to face the death penalty’s manifold injustices.

The state’s death penalty system, Newsom says, “has been, by all measures, a failure. It has discriminated against defendants who are mentally ill, black and brown… It has provided no public safety benefit or value as a deterrent. It has wasted billions of taxpayer dollars. Most of all, the death penalty is absolute. It’s irreversible and irreparable in the event of human error.”

He also voiced strong opposition when, during the first Trump presidency, the administration resumed federal executions. But the governor needs to go further: To cement the status of the death penalty as a relic in the Golden State, Newsom should issue a wholesale commutation of the death sentences of the more than 500 people who could face execution if a Republican wins the governorship in 2026.

Two-thirds of these inmates have been on California’s death row for more than 20 years, and dozens of individuals have been there for more than 40 years.

If Newsom removes the possibility that they would ever face execution, he will deliver the kind of decisive blow against capital punishment that will reverberate across the whole country.

The occasion of the 20th anniversary of his state’s last execution would be a good time to take that step.

But whether he does so or not, one thing that we can learn from California is that stopping executions does not lead to a spike in homicide rates. In fact, after two decades without an execution, homicide rates in that state are at historic lows. In 2024, the rate was, according to the state’s Department of Justice, 4.3 killings per 100,000 people—far below what it was in 2006. It fell again last year.

As Newsom put it on Jan. 8, in his State of the State address:

The last time homicides were this low in Oakland, the Rev. Martin Luther King Jr. was visiting Joan Baez at Santa Rita Jail to commend her on her recent arrest in protest of the Vietnam draft. Killings haven’t been so rare in San Francisco since superstar Marilyn Monroe wed baseball legend Joe DiMaggio at City Hall. And violent deaths in the city of Los Angeles fell to rates not seen since the Beatles played Dodgers Stadium, their penultimate public show.

And just for a little perspective, in 2025 Florida carried out nearly half of all executions in the United States, and California’s  homicide rate was still lower than Florida’s.

The experience in California confirms what many scholars have found. The death penalty is not an effective deterrent and does not make us any safer.

A study of the deterrent effect of the death penalty, published one year before Allen’s execution, offers a good example of their findings. Emory University law professor Joanna Shepherd examined 27 states “where at least one execution occurred during the sample period.” Executions, she found, “deter murder in only six states.”

In addition, it turned out that:

capital punishment … actually increases murder in thirteen states, more than twice as many as experience deterrence. In eight states, capital punishment has no effect on the murder rate.

Shepherd concluded that “executions have a deterrent effect in only twenty-two percent of states. In contrast, executions induce additional murders in forty-eight percent of states.”

It is true that we cannot say that California’s pause on executions caused its homicide rates to fall. But what we can say is that calling a halt to executions has not made Californians less safe.

Of course, in California the death penalty remains on the books, and some of the prosecutors in the state continue to seek the death penalty. It still pays an extraordinarily high cost in taxpayer dollars for doing so.

Research reported in 2010 showed that California taxpayers have spent more than $4 billion on the death penalty since it was reinstated in 1977. Today, the state spends more than $100 million on death penalty litigation. Over 20 years, that amounts to $2 billion.

And California is not alone among states with the death penalty on the books that have not executed anyone in five, 10, or more years. What happens in places like Ohio, Pennsylvania, Montana, and Kansas, which I call “death penalty swing states,” will go a long way in determining the fate of capital punishment in this country.

California can set an example for them to follow. That’s why the 20th anniversary of its last execution and any decision Newsom might make about clemency are so important.

As he considers what to do, he might examine what other governors have done in the past.

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In the year that California executed Clarence Ray Allen, no governor commuted the sentence or pardoned anyone on death row. Since then, chief executives in such death penalty hot spots as Oklahoma, Georgia, and Texas have exercised their clemency power to spare the lives of people in their state who were condemned to death.

Newsom has the opportunity not only to join them, but to go one step further by issuing the largest mass death penalty clemency in American history. Despite the length of time that his state has gone without an execution, that will not be an easy choice.

However, as he explained in his State of the State address, “The story of California has never been the story of ease. It has been the story of effort, strengthened by trial and enlarged by the people who refuse to give up on one another.”

Twenty years after Clarence Allen’s death, Newsom has the chance to add an important chapter to that story and show that his state never gives up even on those who have been condemned to die.

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