A new twist in defending against red light tickets has occurred in recent years, with the introduction of photographic automated enforcement systems, also known as red light cameras. These devices work by triggering a camera as a vehicle passes over a sensor in the intersection when the light is red. The camera takes pictures of the vehicle’s front license plate and driver. A citation is then mailed to the vehicle’s registered owner, supposedly after a police officer checks the photo of the driver against the driver’s license photo of the registered owner.

The Driver Is Usually Liable, Not the Owner

In most of the states that allow photo enforcement of red lights, the law states that the driver, not the vehicle’s owner, is liable for the ticket. (New York treats red light camera violations like parking citations, making registered owners responsible without regard to who was driving when the camera snapped the photo.) In states where the driver—not necessarily the owner—is responsible for the ticket, and the owner was not driving at the time of the violation, the owner can fill out an affidavit, swearing that he or she wasn’t driving when the violations occurred.

Get the Photos

The first step to take in fighting a ticket issued by a red light camera device is to get the photographs. In some states, those photos will be mailed to you along with the citation. In other states you will have to make a "discovery” request to get them. When you get the pictures, examine them to see if the picture of the driver bears any likeness to you, and whether the license plate number can be read clearly. For example, Maryland Sen. Alex Mooney successfully fought a ticket for running a red light in 2003 despite a red light camera showing his car speeding through an intersection. Why? Because Mooney was able to prove to a judge that a car thief was behind the wheel of his car.

Was the Device Working Properly?

At a trial, the government (whether represented by the police officer or a prosecutor) must present evidence on how the device works and that it was working properly on the day the citation was issued. The prosecution must also present the camera’s photos showing the vehicle’s license plate and the driver, along with the driver’s license photo of the vehicle’s registered owner.

Possible Defenses

If the images are clear, you can consider mounting the following defense: If no employee from the company that maintains the red light camera device shows up to testify, you should object to the photos being admitted into evidence, saying, "Your Honor, since no one has appeared to authenticate the photographic evidence, I object to such evidence for lack of foundation.” If the photographs are excluded, there is no evidence to convict you. (On the other hand, if the judge allows the photos in evidence over this proper objection, you may later have a basis for an appeal if found guilty.)

If the photos are allowed into evidence but the images are not clear, you can consider challenging the photo’s clarity, arguing that the evidence is not convincing enough to convict you. You should not agree to testify unless you can truthfully say that you were not driving the vehicle at the time the picture was taken.

If you ran the light to avoid a serious accident or harm to others, you should make that argument, and it’s possible that the judge may find that you acted out of "necessity,” which may be reason enough to find you not guilty.

In some states, another possible defense to a red light ticket is that of missing or non-visible posted signs that are supposed to warn of photo enforcement. First read the law carefully to find if your state has laws about such warning signs.  If you got the ticket in a state that does have specific rules about where and how such warning signs must be posted, go back to the intersection to investigate whether the signs there comply with the law. If they don’t, and you prove that to the court with photos and diagrams, you have a good chance of beating the ticket.

Source: http://www.nolo.com/legal-encyclopedia/free-books/beat-ticket-book/chapter7-3.html