Bookmark and Share

This is an information article about the technology used by police for photo enforcement and the technology citizens use to avoid or circumvent photo enforcement.

Police Technology

The primary speed enforcement tool used by police is photo radar. In the 1950’s a rally car driver, Maurice Gatsonides, invented the first speed radar as a way to improve his racing time.

Gatsonides soon after founded a company, Gatsometer BV, which developed the first radar for use with road traffic. Gatsometer BV is now the world’s largest supplier of photo radar cameras, commonly called “Gatsos.”

It took until the 1990’s for photo radar to innovate significantly—through  the introduction of digital cameras. The major advantage this provided was much faster processing, through image transferring to a central processing location.

Today, photo radar is used primarily in three types of programs: fixed speed cameras, which are installed on the side of roads or underneath overpasses; mobile unit speed cameras, such as police vans; and red-light cameras, which detects either running a red light, speeding through a light, or both.

In the early 2000’s a new technology emerged — Automatic Number Plate Recognition (ANPR), also referred to as Automatic License Plate Recognition (ALPR) in the United States.

ANPR is able to capture license plate numbers using high quality digital imagery and optical character recognition software. The plate number can then be processed real-time with a police database.

In the United Kingdom, ANPR is used nationwide, and not just for traffic enforcement. Under the government’s “Project Laser” program, ANPR cameras log all vehicles driving on the national road network, enabling the tracking of all vehicle movements.

ANPR cameras are often used to track down stolen vehicles or drivers with suspended licenses. While many law enforcement agencies report a high effectiveness rate for ANPR cameras, the technology faces heavy criticism from civil liberties advocacy groups, especially in the United States.

In Phoenix, AZ, one of the most active photo enforcement cities, photo radar is used along-side a newer technology: piezo strips. Piezo strips can trigger an electric signal once it recognizes pressure. When two strips are positioned at a fixed distance from each other, the speed of a car can be calculated as it drivers over the two strips and triggers the electric signals.

These devices, installed and operated by Redflex, are used on both streets and interstates in the Phoenix area.

Citizen Technology

The most common countermeasure used by citizens is radar detection devices. Radar detection has been around for over a decade, but in the last few years the technology has improved significantly, often in response to advances in photo enforcement programs.

As some photo enforcement programs switched from radar to laser speed detection, laser detection devices have also showed up on the market.

With the advent of Web 2.0, the internet has begun to play a significant role in the technology race. Web sites like provide a host of solutions for citizens to avoid or become aware of traffic enforcement programs such as photo radar. provides a Google Maps mash-up with user-submitted locations of photo radar fixed-camera and red-light camera locations. The site claims to have more than 50,000 cameras logged on their maps.


Beginning in 2008, provided files for downloaded for citizen’s GPS devices. In January of 2009, they released a free iPhone Application that, if used with AT&T’s 3G network, can warn users of upcoming photo-radar cameras.

Bookmark and Share