Jury still out on use of gunfire detectors near Johns Hopkins

The incident on Charles registered as a gunshot but was picked up by only three sensors because one was broken. Martin L. Beauchamp, the security systems manager for Hopkins and a retired Baltimore police major, said officers responded but found nothing.

He sent his security guards out the next morning "and we found a pack of firecrackers" near a tree 9 feet southwest of the back of a rowhouse - precisely the location the computer had spit out. Beauchamp said that had the fourth sensor been working, the system probably would have noted the sound but recorded it as unlikely to be gunfire.

The second hit came just a few hours later at West University Parkway and Canterbury Road, near Homewood Field, in the middle of the block and the middle of the street. Beauchamp said two security guards were nearby and also heard the noise. "They thought it was a gunshot or a car accident," he said. "We weren't able to figure out what it was."

Other cities, including Washington, use similar detection systems, though Baltimore officials have expressed skepticism about their value. City police will be at Hopkins on New Year's when celebratory gunfire sometimes drowns out fireworks, and perhaps that will be a good test.

"It's another layer of high technology," said Edmund G. Skrodzki, the director of Hopkins security and a retired U.S. Secret Service agent. So far, he said, he's impressed by the system, and it seems to me with all the reports of gunfire, city police might want to explore this.