The U.S. is testing new surveillance technology in Iraq that uses infrared sensors to determine the location and make of guns fired in a combat zone.

A New Jersey city is the latest to deploy a network of high-tech acoustic detectors that can detect and triangulate gunshots. The system, which cost $300,000, can triangulate the location of gunfire within three to five seconds and relay the information to officers.

Police departments around the country turn to sound-analysis technology to detect and report gunshots.

Chicago will augment its camera surveillance of high-crime areas with a new listening device that can detect the sound of gunfire and lead to quick dispatch of police to the location.

The US army is currently testing an experimental system that can detect sniper fire by using a ground-based carbon dioxide laser to measure the movements of dust particles in the air caused by the shock wave of the bullet.

A laser capable of pinpointing sniper fire and a system that could alert troops to remote-controlled explosives are being tested by the US military and could be deployed in combat as early as 2004.

The author examines the legality and social costs of the Shot Spotter and FaceIt, two recent law enforcement inventions that have been implemented to mass monitor the public. He probes the Constitutionality of these technologies and whether they have blurred the distinction between what is public and private and offers policy prescriptions for restoring the balance.

Police praise a new high tech system that allows them to record and track gunfire, but privacy advocates fear it could be abused.