Speed cameras have become a common way of trying to reduce speeding and keep people safe on the road. These cameras would automatically trigger the process of issuing a ticket to drivers that the camera catches speeding, all without the need to pull them over or chase them down.
The expectation here is that when drivers know they are being watched and that penalties can issue for any violations the camera catches, they will control their speed. But do these cameras actually work? Do the controversies around them outweigh the actual benefits?
Concerns with Traffic Cameras
Before we get into the data surrounding traffic cameras, let’s first look at their purpose and the issues surrounding them.
The goal of these cameras is to deter speeding. If drivers see signs that speed cameras are in use, then they do not need to see the presence of a police car to know that they could be ticketed for speeding. However, that does not mean that everyone will listen.
Whenever the punishment for speeding or another safety violation is a fine, those who can afford it might simply pay the fine and never change their behaviors. Plus, with speed cameras, there are other controversies that might make them ineffective.
Reports have noted multiple reasons for failed speed camera systems being dismantled over the years, including the observation that many people just ignore the tickets from these cameras. Pair that with arguments that speed camera enforcement is unconstitutional given the fact that your right to confront your accuser is not protected when your accuser is a camera rather than an officer who can be brought to court to testify about the ticket they issued you.
Especially when it comes to keeping people safe and having them reduce speed, it is not always clear that speed cameras have the desired effect.
Recent Speed Camera Bill in Philadelphia
To look at one example of a hopeful speed camera program, look no further than Philadelphia. Upcoming plans for traffic cameras on Route 13, Route 611, and Broad Street. The bill enabling these upcoming cameras, signed on January 27, 2025, has no citations to studies or practices that demonstrate the cameras will be effective, and there are no legislative goals outlined in the bill itself. However, reporting has seen the mayor citing research from the University of Pennsylvania, saying that traffic cameras save one life per month on Roosevelt Boulevard alone. Similarly, one city councilman has gone on record saying he hopes the cameras will save lives, having seen two traffic fatalities on the block outside his office.
Philadelphia personal injury lawyers are also hopeful that the cameras will save lives, and hope that any safety devices that can reduce speed will have the desired effect. As pointed out in a 2013 study, reducing speed has the biggest impact on reducing the force of a crash when it comes to the physics of a crash.
Studies on Motor Vehicle Safety Brought About by Speed Camera Enforcement
That same 2013 study mentioned above, from the Association for the Advancement of Automotive Medicine, looked into previous speed camera enforcement in Arizona as well as a then-current enforcement program to determine effectiveness. This can also be compared to the Roosevelt Boulevard study the Philadelphia Mayor may have been referencing.
2013 Study
The study pointed out some of the issues we discussed above, such as previous programs’ failures based on people ignoring tickets. However, there was another interesting issue with that previous program’s results: what the study references as “an accordion like effect.” With this, cars would slow down as they approached the speed cameras (given that they can see the cameras and the signs warning about automated speed enforcement), then speed up again after passing the camera.
This study looked at two comparable roads: one control road with no cameras and another with traffic cameras. They looked at three different time periods: before the cameras were installed, while the cameras were up, and a period after the cameras were taken down. Ultimately, that study found that the variation among those times was not statistically significant – that is, there was not a noticeable difference between the road with the cameras and the road without the cameras. The same was true when the cameras were removed; things did not bounce back to being worse without the cameras.
Philadelphia Study
In contrast, the report that Philadelphia’s Mayor seemed to be referencing was a study out of the University of Pennsylvania looking at traffic cameras on Roosevelt Boulevard. The study references a mixture of factors that “make Roosevelt Boulevard so deadly,” including a high number of lanes, 40-45mph speed limits, dense population, and high traffic. That study ultimately found a positive impact of cameras.
The study starts by referencing other positive studies before going into how, with their own data, they compared Roosevelt Boulevard to other surrounding “arterial” roads, employing various controls in the control roads’ qualities, size, etc. Their data did show a statistical difference, and found that the speed cameras likely did have the desired effect of reducing fatalities, even in comparison to the trends on other nearby roads.
Other Problems with Studies and Implementation
As noted above, there are some potential problems with speed camera enforcement and the effect it has on actual speed.
First, people slow down in response to the signs warning about speed cameras. This means that the enforcement and ticketing aren’t necessarily slowing traffic; it’s potentially just the presence of the cameras. The same effect could be achieved by having a police car sit and watch the road. That effect of cars slowing down in the enforcement area might even be achieved with nobody in the police car, all without the expense of installing traffic cameras.
Second, drivers will, as the 2013 study noted, often slow down before the cameras and speed back up again after passing the cameras. One common cause of accidents is changes in speed, meaning that everyone slowing down and then speeding back up again could increase the risks of crashes between cameras, even if it reduces risks in front of the cameras. This could result in a net zero change in safety on the whole road.
Lastly, the U Penn study points out a massive weakness of speed cameras: if the goal is safety, then speed cameras come into the picture when it’s already too late. The cameras in the Roosevelt Boulevard study only send out a ticket when the driver is driving more than 50-55mph. That is, as the study notes, already fast enough to kill a pedestrian. A lower speed threshold would be needed to make a bigger difference in safety.
Ultimately, it seems that speed cameras can have a real effect on road safety and truly save lives. However, like with any problem, it does not appear to be a one-size-fits-all approach, based on the differing results among studies. If we want to keep people safe, we need to lower traffic speeds, and speed cameras are only one tool in that fight – and they have to be implemented properly to achieve their safety goals.
