Last week I attended a conference that looked at speed cameras as a tool that could help in the city's Vision Zero efforts, an initiative to reduce traffic-related accidents and deaths in the city. Philadelphia has among the worst rates of car crashes in comparison to other large cities. We reported in December the city had 11,000 automobile crashes a year on average from 2009 to 2013 that caused 90 to 100 deaths a year. That's a higher rate than is seen in New York, Chicago, and San Francisco, according to a report from the Bicycle Coalition of Greater Philadelphia, which also hosted last week's event.

The panel of legislators, cops and researchers talked about what speed cameras can offer, and what they might mean for Pennsylvania, where authorizing legislation would be needed before they can be installed.

The cameras are similar to red light cameras, or those that take pictures of people who don't pay tolls. They have radar equipment built into them and any vehicle exceeding a certain speed (typical is 10 or 11 miles over the speed limit) get a license plate picture taken and a ticket in the mail. The cameras aren't a secret. Places that use them post signs announcing their presence to encourage people to slow down.

A street that cries out for speed cameras, the panelists said, is Roosevelt Boulevard, the 12-lane route where 23 people have been killed in traffic incidents since 2011, officials said.

"It's a superhighway that goes through a neighborhood," said Philadelphia police captain Francis Healy.

People obeying the speed limit are the exception, not the norm, he said. Last year police wrote motorists 3,600 violations on that road. The road has red light cameras already, and Gustave Scheerbaum, who manages the red light enforcement grants program, said those have reduced crash frequencies at six intersections on the Boulevard.

Another panelist, Wen Hu, a research engineer at the Insurance Institute of Highway Safety, shared the results of her look at the effect of speed cameras in Montgomery County, Maryland, that were first installed in 2007. Over seven and a half years the percentage of vehicles exceeding the speed limit by more than 10 miles went from almost 30 percent to just more than 10 percent. She also credited speed cameras with reducing the number of serious or fatal injuries resulting from crashes in the county by almost 20 percent.

Speed cameras face strong opposition in the state, said State Rep. John Taylor, chairman of the city Republican Committee. They have gotten bad press in Washington D.C., where the Washington Post has done stories, like this, about their unreliability. They are also seen as a way for local police departments to drum up cash. And some people, he said, are philosophically opposed to them.

"It comes from the philosophy that government shouldn't be infringing on us in that way," Taylor said.

All the panelists, though, said the cameras are a positive. Bob Prevedi,  policy coordinator for the Bicycle Coalition, the state should take steps to ensure speed cameras are reliable and functional because the technology will save lives. A bill is pending in the state senate but has not passed.

"We want to work very hard at maintaining the integrity levels that the red light cameras have done so far I Pennsylvania," he said.