ST. LOUIS (AP) -- The first Missouri city to use cameras to catch drivers running red lights may keep issuing tickets, a federal judge has ruled, rejecting claims that the cameras violate drivers' rights.

U.S. Magistrate Judge Thomas Mummert III on Thursday sided with the city of Arnold, which had argued that its red-light cameras didn't break the law.

Arnold, a Jefferson County community of about 20,000 residents, passed a law in 2005 to allow red-light cameras. The cameras record vehicles that run red lights at intersections, with tickets later issued for violations. A federal lawsuit filed last year on behalf of some who had been ticketed claimed the ticketing process was unconstitutional and amounted to racketeering.

Mummert rejected those claims. Plaintiffs attorney Chet Pleban could appeal or file suit in state court to take up issues related to Missouri law. He said Friday he has not yet decided what action might be taken, but he believes legal questions about the cameras remain.

In Arnold, the cameras record a vehicle, not the face of the driver running a red light, Pleban said.

"You can't begin and end with one camera that doesn't identify people, and then take money from them," he said. "That's not right."

In Missouri, if a driver is ticketed by a police officer for running a red light, it's a two-point offense, Pleban said. If the driver is caught by a camera in Arnold, he or she is fined but not assessed points. Pleban questions why the same offense has different penalties.

And he said he's concerned that the tickets issued because of the cameras are used as a way for communities to generate revenue.

The city of Arnold said Friday it planned to issue a statement about the ruling. It has defended use of red-light cameras in the past, with former Mayor Mark Powell saying last year that violations and accidents had fallen sharply since the cameras were installed.

State Rep. Brian Yates, a Republican from Lee's Summit, wants oversight of the cameras to make sure drivers aren't being ticketed unfairly. He would like businesses that provide the red-light cameras to deposit money with the state for audits of the tickets issued and revenue produced.

He suggested that signs could be placed in advance of the cameras so drivers know where they are, and said there has been discussion about efforts to make sure yellow lights last for a standard length of time. In other places, concerns have been raised about yellow-light manipulation that leads to more drivers running red lights, he said.

Yates hopes the judge's order will encourage state lawmakers to take up related legal questions. Some may have been waiting to see if the case resolved matters, he said.

"I basically believe this will provide the Legislature with more motive to address the red-light camera issue," he said.