It was fortuitous for Mayor Luke Ravenstahl that on the day he made a pitch for 220 more security cameras around the city, a set of four such devices proved instrumental in solving the killing of a retired firefighter.

The arrest of two young men in the March 14 killing of Mark Barry was not the first time that security cameras have aided city police in solving crimes. In this case, the cameras are owned by the Brightwood Civic Group on the North Side, just as numerous organizations and businesses operate electronic monitors to protect their own interests.

The city itself has installed 20, and another 40 to 50 devices should be in place by June, all connected with the Port of Pittsburgh and focused on rivers and bridges, according to the city's chief information officer, Howard Stern.

Now, the city, Community College of Allegheny County and Carnegie Mellon University are seeking $16 million in federal stimulus money, enough to pay for 220 more electronic eyes on Pittsburgh streets. The city police bureau would decide where the cameras would go, and they could be easily removed and repositioned based on patterns of criminal activity.

The cameras have proved their usefulness in crime solving, and the city adopted a policy that bans their use to identify and track the activities of individuals who are not engaged in illegal activity. It doesn't allow monitoring of conversations and provides other privacy safeguards, including controlling who has access to the footage recorded. That policy was worked out with input from community groups, the Pittsburgh American Civil Liberties Union chapter, and The Constitution Project, a Washington, D.C.-based civil liberties organization.

But City Council would have to amend it to allow Carnegie Mellon's plans for cameras. Unlike CCAC, which wants to install them on its campus, CMU instead wants access to the data the city cameras collect, information that would be used for research.

Careful study should be undertaken and public input gathered before moving in that direction, as well as vastly expanding the use of cameras on city streets. Success so far shouldn't blind Pittsburghers to the possible civil liberties threats inherent in a tenfold increase in city cameras.

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