The answer appears to be no – at least according to one study in DC. According to a Washington Post article:
The District’s red-light cameras have generated more than 500,000 violations and $32 million in fines over the past six years. City officials credit them with making busy roads safer.
But a Washington Post analysis of crash statistics shows that the number of accidents has gone up at intersections with the cameras. The increase is the same or worse than at traffic signals without the devices.
Three outside traffic specialists independently reviewed the data and said they were surprised by the results. Their conclusion: The cameras do not appear to be making any difference in preventing injuries or collisions.
“The data are very clear,” said Dick Raub, a traffic consultant and a former senior researcher at Northwestern University’s Center for Public Safety. “They are not performing any better than intersections without cameras.” . . . .
The Post obtained a D.C. database generated from accident reports filed by police. The data covered the entire city, including the 37 intersections where cameras were installed in 1999 and 2000.
The analysis shows that the number of crashes at locations with cameras more than doubled, from 365 collisions in 1998 to 755 last year. Injury and fatal crashes climbed 81 percent, from 144 such wrecks to 262. Broadside crashes, also known as right-angle or T-bone collisions, rose 30 percent, from 81 to 106 during that time frame. Traffic specialists say broadside collisions are especially dangerous because the sides are the most vulnerable areas of cars. . . .
The results were similar or worse than figures at intersections that have traffic signals but no cameras. The number of overall crashes at those 1,520 locations increased 64 percent; injury and fatal crashes rose 54 percent; and broadside collisions rose 17 percent.
Hat tip: EPIC West Blog