For proof, the NRA points to New York City's 1991 ban on certain rifles and shotguns. The city used its registration database, created in 1967, to notify more than 2,300 New Yorkers that they must surrender, dismantle or take weapons out of the city, according to an NRA website.
In Michigan, all handgun purchases must be detailed on a "pistol sales record" that shows the buyer, seller and information about the make, model and serial number.
The requirement, instituted by the legislature in 1927, was targeted by the NRA, though legislation to undo it failed in recent years. It gained momentum last year as Republicans took control of the governor's office, the state House of Representatives and Senate, said Sgt. Chris Hawkins, legislative liaison for Michigan State Police, which oversees the registry.
The bill passed the House and was awaiting Senate action when police arrested geologist Raulie Casteel and charged him with the October driver shootings, Hawkins said.
Hawkins told lawmakers the database helped lead to the suspect. Both Hawkins and Rick Ector, a Detroit firearms instructor who pushed for the bill, said the arrest saved the database.
The registry helped prioritize one of more than 2,000 tips to police, Hawkins said. The information about the shooter's possible license-plate number showed the car was registered at the same address as a 9 mm Ruger, he said.
Police had already been looking for such a gun because of ballistic evidence, said Clarence Goodlein, public safety director for Wixom, a suburb where most shootings happened.
Police arrested Casteel 20 days after the first shooting. He pleaded not guilty to more than 60 felony charges, including terrorism and assault with intent to murder, both punishable by life in prison, said Douglas Mullkoff, his attorney.
The gun registry may have "meant the difference between someone getting killed by gunfire and someone not," Hawkins said.