The city was given the green light to crack down on more drivers running red lights with the enactment this week of legislation that allows it to double the number of cameras at intersections to catch offending drivers.
The law, which was signed by Gov. George E. Pataki, raises the total number of so-called red light cameras the city can install to 100 from 50.
The cameras, which photograph a vehicle if it enters an intersection after the light has turned red, generate millions of dollars in fines, but officials said they were most important as a way to reduce accidents.
“The revenue is nice, particularly to offset the cost of the program, but from our perspective it’s a safety issue,” said David Woloch, a deputy transportation commissioner for the city. “To reduce fatalities and injuries is at the top of our list.”
Last year, the city issued 306,117 tickets, each of which carries a $50 fine, to the owners of vehicles caught on the cameras.
The cameras, which were first installed in the city in small numbers in the mid-1990’s, have been criticized as representing an invasion of privacy, although city officials say the cameras photograph cars from the rear and would not normally make it possible to identify a driver.
Critics have also claimed that the reduction in the number of head-on or side-impact collisions resulting from the cameras is offset by an increase in rear-end collisions that occur when drivers slam on the brakes at the last minute for fear of being caught by the cameras in the act of running the light.
To bolster its support of the program, the city provided an analysis of the number of injuries that followed accidents at intersections where 44 cameras were installed in 2001 and 2002. The study compared the 12-month period before installation of a camera at an intersection with the 12-month period after its installation, and found that over all, the number of injuries fell by an average of 24 percent.
Information provided by the agency, however, did not indicate if the number of accidents also decreased or if there was a change in the types of accidents.
Mr. Woloch said the city had been lobbying the State Legislature for several years for permission to increase the number of cameras, which had been set at 50 by state law.
The city currently has 50 digital cameras that can be mounted at 75 different intersections throughout the five boroughs. Mr. Woloch said that 100 cameras would be in operation within six months and that the Transportation Department would eventually install equipment allowing it to rotate the cameras among 150 locations around the city.
There are also 200 nonworking “dummy cameras” set up at intersections in the city, meant to trick drivers into believing they may be caught at those intersections as well.
The city will not reveal the locations of the cameras, although clearly some drivers, particularly those who have received tickets or who live near intersections outfitted with cameras, know where they are.
If the locations of the cameras were widely disseminated, drivers might obey the traffic signals at those intersections and then feel free to run red lights elsewhere, according to Kay Sarlin, a spokeswoman for the Transportation Department.
The city says that since 1993, it has spent roughly $85 million on the red light camera program and has taken in about $130 million in fines.
Officials said the cameras were effective in discouraging drivers from running red lights. Data shows that the number of violations captured by the cameras decreases significantly over time, as drivers become aware of them.