A SPIRITED DEBATE about the use of automated traffic cameras was abruptly derailed in the state Senate Thursday evening after a Republican senator moved to table the bill.

Under Senate rules, a single senator has the power to force a bill to be held. After a close debate about the scope of the traffic camera program, Sen. Ryan Fattman of Sutton said he believed Minority Leader Bruce Tarr of Gloucester was “gaveled down inappropriately” and tabled the bill.

The bill would let municipalities install automated traffic cameras to issue violations for offenses like speeding and running red lights.

Senators voted for an amendment supported by the  bill’s sponsor, Sen. Will Brownsberger of Belmont, to limit the scope of the program to 10 communities. Tarr then proposed a more limited program – a three-year pilot involving three to five cities.

After Tarr argued for his amendment and Brownsberger argued against it, Tarr yelled out to be recognized to speak again, but Sen. Cindy Friedman of Arlington, who was presiding, called the vote. Tarr’s amendment was rejected by one vote, 18-19.

A Tarr aide said afterwards that Tarr is willing to rework his amendment to extend the length of the proposed pilot program. Some of the concerns Brownsberger raised were about the cost and effort to municipalities if they were to install cameras only to have the pilot program end.

The delay could give Tarr a chance to rewrite his amendment and sway another vote – and will give lawmakers more time to debate the controversial policy.

Supporters say traffic cameras will reduce crashes involving pedestrians and cyclists. “In our busy urban communities, the problem of death on our streets is a very real issue,” Brownsberger said. “In many communities, there is a volume of traffic violations that cannot be addressed by the available police resources.”

Sen. Pat Jehlen of Somerville said in her district, which covers parts of Cambridge, Somerville, Medford and Winchester, 120 pedestrians and cyclists were injured in the last two years.  She named four people killed last year while crossing the street. “This bill will save lives,” Jehlen said.

But opponents worry about privacy, civil liberties, the cost to drivers and municipalities, and the cameras’ effectiveness.

Tarr said at least nine states explicitly prohibit the use of traffic cameras to enforce red light violations or speeding, and the 23 states that allow them have had mixed results. Tarr said the collection of photographs of vehicles raises privacy concerns “about what will happen with the information, how long it will be retained, what it will be used for, who it will be disseminated to, how it will be protected.”

Sen. Jamie Eldridge, a progressive Democrat from Acton, worried that cameras placed in urban areas will have a disproportionately negative impact on people of color.

Under the bill, traffic cameras could ticket drivers who fail to stop at a red light; speed; make an illegal right turn on red; pass a school bus when warning signals are on; block an intersection; or block a bus lane.

Where the speed limit is under 45 miles per hour, a ticket could be issued for speeds at least five miles above the limit. Where the speed limit is 45 miles per hour or higher, a ticket could be issued to drivers going 10 miles over the speed limit.

The maximum fine for tickets would be $25. Citations would not go on a person’s driving record or be used for an insurance surcharge. A person who ignores five citations could have their license suspended.

The citation would be sent to the car owner or the person renting a car. There would be an appeals process.

Cities and towns could only install one camera per 2,500 residents. The locations would have to be approved by city government at a public meeting, and signs would be posted on the road. A municipality with a population of under 20,000 could not install a camera.

Brownsberger said the decision made on the floor to limit the program to 10 municipalities approved by the Department of Transportation ensures the program will be available to the few larger urban communities that are asking for it – places like Boston, Brookline, Cambridge, and Somerville – while giving policymakers a limited pool to study how it is working before considering an expansion.

Similar proposals have existed for years. The late Boston mayor Thomas Menino wanted to install red light cameras and cameras that detect people who improperly pass school buses. But none of the proposals have before made it to a House or Senate vote.

House Transportation Committee Chair William Straus said lawmakers have worried that the only financial benefit of these cameras in other states has gone to camera vendors. Senate Transportation Committee Chair Joseph Boncore said installation can cost municipalities up to $100,000 per camera, and monthly service contracts range between $5,000 and $10,000 per camera. That means a city would have to ticket 4,000 to 5,000 cars to break even.

Straus also said it is not clear that there is a safety benefit. He pointed to reports that the cameras might cause an increase in rear end collisions as drivers brake quickly.

Brownsberger said the bill addresses financial concerns by prohibiting vendors from being paid based on the number of violations issued or the amount of revenue generated. It only lets municipalities recoup their costs; additional money would go into a state transportation fund.

Brownsberger said red light cameras may not reduce collisions between cars, but they will reduce more dangerous collisions with pedestrians, and cameras are effective in limiting speeding.

To address privacy concerns, Brownsberger said a record would be made only when a violation occurs and destroyed when it is resolved.

Under the bill, the Department of Transportation would do a study after three years to examine the program’s effectiveness and implications for public safety, congestion, and racial equity.

A report released in August by the AAA Foundation for Traffic Safety found that 939 people were killed in 2017 due to drivers running red lights. Mark Schieldrop, a spokesman for AAA Northeast, said the organization has not taken a position on Brownsberger’s bill, but generally AAA supports the use of traffic cameras only at intersections that have proven to be dangerous and in collaboration with law enforcement, traffic engineering measures, and educational campaigns. Cameras need to be evaluated regularly. “You can’t just stick automated enforcement up and call it a day,” he said.

The name of the senator who was presiding over the debate has been corrected.