California has some of the nation’s toughest gun laws, including mandatory background checks and a 10-day waiting period on all firearm purchases.

This year, after a heavily armed couple killed or wounded 36 people at a holiday party in San Bernardino, state lawmakers took additional steps to outlaw weapons designed to kill as many people as possible, as quickly as possible.

Beginning in 2017, semi-automatic rifles equipped with “bullet buttons,” a feature allowing rapid replacement of ammunition magazines, will be banned in California. So will the sale or possession of ammunition magazines with a capacity of more than 10 rounds.

Also, starting in 2019, background checks will be required for ammunition sales, and ammunition sales will be prohibited to people ineligible to own guns due to felony convictions, mental health issues or restraining orders related to domestic violence.

Proposition 63 on the Nov. 8 ballot covers much of the same ground. But it was drafted without legislative oversight and has conflicting provisions that could result in litigation, complicating implementation of the new state laws.

Initiatives are supposed to provide an alternative route when the state Legislature fails to act. On this issue, however, legislators have acted. Voters are asked to supersede those laws with Proposition 63. That seems premature. The Press Democrat recommends a no vote.

One area of conflict is the ban on high-capacity magazines, with different exemptions in the law and the initiative. Another is background checks on ammunition sales. Proposition 63 creates a new state permit for buyers, which could be renewed every four years. The new state law requires a check on each purchase. Both avenues are likely to produce litigation, and the conflict between them could present its own legal challenges.

Proposition 63, sponsored by Lt. Gov. Gavin Newsom, isn’t without merit.

In an attempt to thwart straw purchases, the initiative would require people to notify law enforcement within five days after discovering that one of their weapons is lost or has been stolen. Too often, guns are reported lost or stolen only after being used in a crime.

Proposition 63 also would close a loophole in Proposition 47, a 2014 initiative that allows the theft of a gun worth less than $950 to be charged as a misdemeanor. Making that a felony offense means anyone convicted of stealing a gun would no longer be eligible to own or possess a firearm. Such a change requires voter approval, but that could be accomplished separately — and without the friction between other provisions of Proposition 63 and the state’s new gun laws.

As regular readers of these pages know, we are strong supporters of gun safety laws. We applauded the creation of an institute at UC to study gun violence, and we’re disturbed at the resistance in Congress to closing the gun show loophole in the federal law requiring background checks.

Not even the massacre of 20 children and six adults at a Connecticut elementary school was enough to break the logjam in Congress. In California, however, lawmakers have worked to promote gun safety without unduly restricting the rights of law-abiding citizens. Give those measures a chance. Vote no on Proposition 63.