The City Council is set to pass legislation today that makes it easier for victims to sue gun manufacturers and dealers for crimes committed with their weapons.

The measure, which has the backing of the Bloomberg administration, gives crime victims and their families a new way to sue a dealer or manufacturer in, say, Georgia, for a shooting that took place in the Bronx.

The legislation – part of a package that also forbids the sale of more than one rifle or shotgun to an individual within 90 days, and more than doubles fines for state-banned assault weapons – could serve as a model for other cities at a time when the federal government is rolling back gun-control regulation, supporters said.

“This bill will help to shut down the ‘handgun highway’ that brings guns up I-95 from Ohio and Pennsylvania, from states where it’s easy to buy guns,” Council Member David Yassky, the most vocal sponsor of the legislation, said, referring to one hotly disputed measure.

Opponents, however, said the city lacks the authority to force dealers outside the city to comply and has no business trying to supersede federal law.

“It is patently unconstitutional,” the senior vice president and general counsel for the National Shooting Sports Foundation, the firearm industry’s trade association, Lawrence Keane, said in a telephone interview. “A first-year law student would recognize that. It attempts to regulate interstate commerce.”

The provision creates a so-called “code of conduct” for the gun industry. That part of the legislation, supporters said, will pressure the industry voluntarily to adopt more responsible practices by granting them exemption from civil liability. The code holds liable those who sell a person more than one handgun within 30 days, or who fail to conduct background checks at guns shows, if the weapon ends up killing or injuring someone in the city.

The measure, which almost certainly will be challenged in court, applies only to civil cases and leaves it to the plaintiff, not the government, to take action. Both San Francisco and the District of Columbia recently adopted similar laws. The San Francisco measure, which has no exemptions, has yet to be applied and is generally not well regarded.

The legal director of the Brady Center to Prevent Gun Violence, Dennis Henigan, commended the New York City Council, saying the legislation was sensible. It essentially tells dealers and manufacturers how to avoid trouble, he said.

“It’s astonishing that any gun manufacturer would object to this,” Mr. Henigan, who is representing New York City in a lawsuit against several gun manufacturers, said. That suit says manufacturers fuel illegal gun sales through irresponsible marketing and sales practices.

The group of bills won unanimous approval yesterday by the council’s Public Safety Committee, ending two years of hearings and negotiations. Its success was due largely to support from Peter Vallone Jr., chairman of the committee, and the council speaker, Gifford Miller.

But Mr. Yassky took the unusual step of publicly criticizing the council speaker for what he said was Mr. Miller’s insistence that a provision be dropped from the package that would have made it easier to sue those who sell more than 20 guns in a year that are linked to crimes.

“I don’t understand why council members elected by 160,000 New Yorkers cannot vote on an important question in a bill,” Mr. Yassky said during the committee hearing.

“If this provision is controversial, if there are folks that don’t like it, that’s fine. Let’s put it forward. Let’s vote on it. … I think if we want this body to be taken as seriously as it deserves to be taken, then we have to grapple with difficult issues.”

Mr. Miller, who met with Mr. Yassky immediately after the hearing and then appeared with him at a news conference, said that the compromise was part of negotiations and that the excluded measure would have been knocked down in Washington. He also indicated that the number of guns was arbitrary. Mayor Bloomberg, whom Mr. Miller hopes to unseat in next year’s election, was also said to be opposed to that provision.

Mr. Bloomberg told reporters yesterday that he would gladly sign the bills once they reach his desk.

“I hope they pass them,” he said, “and if they do I’d certainly be happy to sign them.”