California Gov. Gavin Newsom calls for constitutional amendment to curb gun access

Newsom, a Democrat, wants to raise the minimum age to buy firearms to 21, mandate universal background checks, impose waiting periods on buyers and ban the civilian purchase of assault weapons.

LOS ANGELES — California Gov. Gavin Newsom has proposed a 28th Amendment to the U.S. Constitution that would restrict gun ownership, a response to what the governor described as an "existential crisis" of mass shootings in America.

In an interview Thursday on NBC's "TODAY" show, Newsom, a Democrat, said he personally supports civilian gun ownership and his proposal would not abolish the Second Amendment.

Newsom's proposed 28th Amendment would, however, raise the minimum age to buy a firearm from 18 to 21, mandate universal background checks, impose a waiting period on gun purchases and ban civilians from buying assault weapons.

The governor said he was frustrated with "a lot of the [gun] laws we've passed being rolled back by the federal courts," arguing that a constitutional amendment would be an appropriate response to a sharp rise in mass shootings in the United States.

To pass the 28th Amendment, Newsom and California lawmakers would need to initiate a nationwide convention to propose the measures to the U.S. Constitution. Two-thirds of all U.S. statehouses would need to agree to the initial meeting, and another three-quarters would need to support the amendment for it to become law.

But Republicans, who control more than half of state legislatures, are unlikely to support the move, and no constitutional amendment proposed by a state has ever become law.

Newsom, however, said he would soon begin cultivating support for the amendment in state legislatures and insisted the proposal is not doomed, arguing there's bipartisan support for the measures in his proposal.

“It’s possible because their constituency demands it,” he said on "TODAY," adding that some federal judges who have recently issued rulings on the issue, which some gun-control advocates have deemed needlessly lenient, “are trying to turn America into Texas.”

“We cannot let that happen," he added.

A Fox News poll in April found that 87% of voters favor requiring criminal background checks on gun purchases, 77% support a 30-day waiting period, and 61% support banning assault weapons.

Last year, Newsom signed a series of gun safety bills into law, ramping up regulations on gun sales and dealers in California.

Michael Mitsanas is a Los Angeles-based journalist. His reporting has appeared in The Diplomat Asia Pacific, NBC News, NBC OUT, NBC News NOW, and MSNBC.

Jacob Soboroff is a correspondent for NBC News and MSNBC and author of "Separated: Inside an American Tragedy."