Localities may one day issue tickets for the crime of driving under the influence of alcohol (DUI) by mail. The Russian firm Laser Systems has developed Alcolaser, a device that uses lasers to remotely detect the presence of alcohol vapors in an automobile. The Alcolaser is available in either in the form of a handheld gun the size of a police radar or in a mounted version designed to work from a moving police car.

The device takes about half-a-second to scan an automobile. According to the manufacturer, the laser has a range of 65 feet and can test vehicles moving at up to 75 MPH. Laser Systems claims that Alcolaser can detect amounts as small as a quart of beer or 3.5 ounces of vodka without being fooled by other sources of ethanol that might be present in a passenger compartment.

An individual with a blood alcohol content of 0.10 would on average exhale enough alcohol vapors to bring the level in a car with the windows closed to 3 parts per million within 30 minutes. The level would be lower in a vehicle with the ventilation system active. Alcolaser takes advantage of spectroscopy, through which light hitting a specific type of molecule is scattered in a specific way. The shift in the energy content of the light differs based on the type of molecule hit, allowing one to detect the presence of a particular substance.

The method used would be incapable of distinguishing between a sober driver and a drunk passenger. It would also be fooled by beer spilled in the passenger compartment. Despite the limitations, the device has been demonstrated at a number of international trade shows and the Russian police are reportedly interested in testing the equipment. The firm already supplies a number of products to various branches of the Russian government.