Sharp eyes and a selective memory are what the city of Pittsburgh wants in a security camera system, according to a proposed privacy ordinance sent to City Council yesterday.

"We're trying to strike a balance here," said Public Safety Director Michael Huss, between "privacy and utilizing this camera system in what we think will be an effective way for our Police Bureau."

Privacy experts liked the proposed rules for what will eventually be a broad network of electronic eyes both Downtown and in neighborhoods but said vigilance is needed as the city picks a vendor, writes internal rules, and deploys cameras.

"I doubt there is a camera network vendor in the country who doesn't have plans to sell cities more invasive surveillance systems," said Marc Rotenberg, executive director of the Electronic Privacy Information Center, based in Washington, D.C.

There is also concern that the city could write internal, secret exceptions to the ordinance's privacy safeguards.

The camera system envisioned by Mayor Luke Ravenstahl's administration would watch public areas, starting Downtown and on the riverfronts and bridges, and later expanding into neighborhoods. They would record images only -- not sound.

Details of the camera deployments aren't yet set. The city plans to invite some 100 firms to submit proposals this summer, and pick one by October based on price, scope and technology. It hopes to start placing cameras by year's end.

Council demanded a privacy policy in September when it authorized $3.45 million in spending -- mostly from a federal grant -- on the riverfront cameras and computer software. It may discuss and vote on the proposal as early as Wednesday.

Under the ordinance, the cameras could be pointed only at public areas experiencing a pattern of crime that surveillance could help address. The neighborhood would have to support the deployment, and residents could appeal to a five-member panel if they wanted a camera removed.

City Information Systems Director Howard Stern said that except in emergencies, no one would be watching the feeds from the cameras. The footage would go straight to computer disk, to be overwritten after one week, unless it was flagged for use in an investigation or court case.

Mr. Huss said that perhaps a dozen city employees would be authorized to search the footage. Any employee manipulating the system to watch someone not suspected of criminal activity or intent could be fired.

The policy wouldn't govern privately owned camera systems, except those bought by neighborhood groups using city funds.

The Department of Public Safety would write rules to prevent the use of cameras to discriminate against people on the basis of race, age, gender, sexual orientation or other traits. Those rules, though, wouldn't be released to the public.

Also kept under wraps would be exceptions to the ordinance's bans on the use of technology that recognizes faces, tracks individuals, or inserts personal information into the video file.

Those are "technologies that are particularly intrusive on individual rights," said Sharon B. Franklin, senior counsel at The Constitution Project, a Washington, D.C.-based rights group that provided the framework for the city's policy. She said police should need a warrant to target individuals.

The ordinance would let the Department of Public Safety write rules for tracking individuals, and Mr. Huss said they would not be available to the public.

The city generally keeps police procedures secret.

The possibility of secret exceptions to the rules worried Witold Walczak, legal director of the American Civil Liberties Union of Pennsylvania.

"How do you know that the regulations are not going to override all of these nice rules that you see in the ordinance?" he asked.

He questioned whether cameras were the best use of the "huge amount of money" a full network will cost but called the privacy policy "one of the better efforts to protect civil liberties that we've seen."

Fresno, Calif., has been working since 2006 toward a 200-camera system and already used it to solve one shooting and many lesser crimes, said Jeff Cardinale, public information officer, for that city's police department.

This year Fresno is spending $500,000 to upgrade so that cadets can watch live camera footage around-the-clock.

Washington, D.C., had what both The Constitution Project and the Electronic Privacy Information Center viewed as a good privacy policy. But now the city wants to link nine agencies into a 5,200-camera system that would have what the organizations view as a loophole-plagued policy.

"You do need to keep your eye on it," said Ms. Franklin. "I think that the way Pittsburgh is approaching it from what I've seen at this point will hopefully address this in an up-front manner."