California will double the taxes on guns and ammunition and use the money to pay for more security at public schools and various violence prevention programs under a new law Gov. Gavin Newsom signed Tuesday.

The federal government already taxes the sale of guns and ammunition at either 10% or 11%, depending on the type of gun. The law Newsom signed adds another 11% tax on top of that—making it the only state with its own tax on guns and ammunition, according to the gun control advocacy group Brady.

Newsom—a potential Democratic candidate for president beyond 2024—has a reputation as one of the country’s most liberal governors. But he has often refused to raise taxes, even for causes he supports like combating climate change.

But it would have been difficult for Newsom to veto this tax increase, given his outspoken support for gun restrictions at the state and national level. Newsom is in the middle of a national campaign to amend the U.S. Constitution to restrict gun sales to people over 21, require extensive background checks, impose a waiting period for purchases and ban the sale of assault-style weapons. Restrictions like that are in place in some states, but not in the Constitution.

That campaign is unlikely to succeed, given the political makeup of the other state Legislatures Newsom needs to convince. But it has put him at the forefront of an issue at the top of many Democratic voters’ lists.

“These laws will not make us safer. They are an unconstitutional retaliatory and vindictive response to the Supreme Court’s affirmation that the Second Amendment protects an individuals’ right to choose to own a firearm for sport or to defend your family,” Chuck Michel, president of the California Rifle and Pistol Association said. “They are being challenged, and the second they are signed, the clock starts ticking towards a judgment striking them down.”

Also on Tuesday, Newsom signed a law overhauling the state’s rules for carrying concealed weapons. The new rules are a reaction to a new standard for interpreting the nation’s gun laws that the U.S. Supreme Court issued last year. California’s new law bans people from carrying guns in nearly all public places—including public parks and playgrounds—public demonstrations and gatherings, amusement parks, churches, banks and any place where alcohol is sold.

Newsom also signed a law that, starting July 1, 2028, would require all semiautomatic pistols sold in California to have microstamping technology. That means each bullet would have a unique marking making it easier for law enforcement to trace the gun it was fired from back to its owner.

No other state has a special tax just for guns and ammunition, though some local governments do. Tennessee once had a 10-cent tax on shotgun shells, but that tax was repealed in 2019. Pennsylvania collects a $3 surcharge on gun sales to pay for background checks. Fees on California gun purchases currently total more than $37, with most of that money paying for background checks.

“Taxing firearm sales to fund violence intervention programs is essential to interrupting the cycle of violence and stopping gun violence before it begins, and we encourage other states to follow suit,” said Kris Brown, president of Brady.

The federal tax on guns has been in place since 1918 and has survived multiple lawsuits. The money from that tax goes to the states, who use it to pay for wildlife conservation and hunter-safety programs.

The California Rifle and Pistol Association has promised to challenge California’s new tax in court. A legislative analysis of the law Newsom signed on Tuesday said it is now an “open question” whether a lawsuit challenging the tax would be successful.

The tax has some exceptions. It would not apply to police officers and it would not apply to businesses with sales of less than $5,000 over a three-month period. State officials estimate it would generate about $159 million annually.

The law says the first $75 million of that money must go to the California Violence Intervention and Prevention Grant Program. The program has funded projects targeting young people in gangs, including sports programs, life coaching and tattoo removal.

The next $50 million would go to the State Department of Education to boost security at public schools. That includes things like physical security improvements, safety assessments, after-school programs for at-risk students and mental and behavioral health services for students, teachers and other school employees.

California has some of the lowest gun death rates in the country, ranking 43rd out of 50 states with 9 deaths for every 100,000 people, according to 2021 data from the Centers for Disease Control and Prevention.