House leadership’s bill strengthening Massachusetts’ gun laws was revealed Tuesday in the wake of the nation’s latest gun massacre, this one by a disturbed misogynist who killed six in a murderous rampage in California before apparently killing himself. Although Massachusetts is an oasis of relative sanity in America when it comes to gun regulation, it can do better and it will when this bill becomes law.

The legislation unveiled on Beacon Hill, the most comprehensive upgrade to gun laws in two decades, is based closely on the recommendations of a task force established by House Speaker Robert DeLeo in the wake of the school shooting in Newtown, Conn. in December 2012 that left 20 children and six adults dead. It closes one weakness in Massachusetts’ law by requiring the state to join a national instant criminal background database that would include relevant mental health information.

In other ways, the bill strengthens existing laws. Police chiefs will expand suitability checks that police chiefs conduct on applicants for concealed weapons permits to rifles and shotguns. Background checks for all private gun sales would be mandatory and penalties would be increased for those who fail to report stolen firearms or who carry a gun on school grounds. Massachusetts has one of the lowest rates of any state for gun-related fatalities, which proves that strict gun laws work, but as Northeastern University Professor Jack McDevitt, who headed the task force, said Tuesday, laws "can be even stronger and they can make us safer."

Mr. DeLeo observed that "in the face of continued absence of federal leadership," states must act, and while true, Washington’s failure to act means that Massachusetts is to some extent at the mercy of states like New Hampshire with weak gun laws. With the National Rifle Association having bought off and/or intimidated much of Congress, more states must follow Massachusetts’ example.

With this legislative session ending on July 31, the House must pass this bill, reconcile it with Senate legislation and get it to the desk of Governor Patrick, who supports further gun reform, before it gets bogged down in the end of session frenzy. That means ignoring special interest delaying efforts and doing what is right for the state and its residents.