DENVER -- A county judge dismissed four photo-radar tickets, prompting the people who won the cases to consider challenging the entire program.

Judge Mary Celeste Monday tossed out the $40 tickets after saying that Denver apparently broke its own law by allowing a private contractor to prepare and send the summons and complaint to those accused of speeding.

Celeste said that city law allows only the police department to prepare and send the complaint. The judge also said the system may illegally reward the contractor for the number of photos it takes.

The ruling puts the entire photo-radar system into question, said Gary Pirosko, a lawyer and former sheriff's deputy whose two tickets were dismissed.

"We're relying on technology in a situation where we'd normally rely on the human judgment of the police officer," Pirosko said.

Denver uses cameras in white roadside vans to catch speeding motorists and their license plates on snapshots. Boulder and Fort Collins also use photo radar to catch speeders. Tickets are normally mailed to violators.

The decision affects only the four tickets in question, but Pirosko and two other defendants are considering whether to challenge the entire program.

City lawyers said they had not reviewed the ruling and declined to comment. Police officials didn't return requests for comment.

Critics, including some legislators, argue photo radar is an invasion of privacy. They also contend that cities see it as a way to make money rather than keep the roads safe.

A law says the city can pay the contractor only for the value of the equipment, not for the number of pictures taken or number of successful tickets issued. Celeste said the city pays the contractor based upon the images, not the fair-market value of the equipment.

Celeste rejected a scattershot of claims by ther defendants that photo radar violated several provisions of the U.S. Constitution.