Police declined yesterday to estimate how many of the illegal guns seized in the city came from Maryland sources.
But Daniel Webster, who consulted on the mayor's plan and is a co-director of the Johns Hopkins Center for Gun Policy and Research, said that 70 percent of the guns used in city crimes were sold by Maryland gun dealers in 2003, the last time that gun trace data were available.
Webster studied efforts to suppress black market gun sales in several Midwestern cities, including Chicago and Detroit. "After these enforcement initiatives were launched, the flow of new guns into the market declined substantially," he said.
The exception, he said, was Gary, Ind. "They didn't really target the dealers," he said. "They didn't do any prosecutions and get the message out. You have to do this with publicity."
Dixon also wants to create a new data-gathering tool called GunStat. "This will allow for better supervision of violent criminals. Illegal guns and the criminals who have them are a serious threat," she said.
Hamm said that the data likely will not be made public because it might compromise broader investigations against people and stores that have questionable sales practices.
Dixon said she does not expect that any of her proposals will require substantial additional city funding: "We're just going to be doing it a little smarter, a little better."