Police departments throughout California are equipping patrol officers with alcohol-sensing flashlights.  The PAS IV Passive Alcohol Sensor "sniffer" flashlight looks like and functions as a normal flashlight but also incorporates a sensor that can detect air-borne alcohol molecules.  The police officer making a traffic stop simply pokes the flashlight into the stopped vehicle's window.  A small pump in the device "inhales" air from the passenger compartment which is analyzed by an electronic sensor.  Green and red indicators then light up to show the officer the level of alcohol detected in the car.   

A problem with the "sniffer" flashlight is that certain non-alcoholic food and cosmetic substances can fool it into producing false positives.  Reportedly, mouthwash, cologne and even soy sauce on the breath can trigger the device.  It also is indiscriminate as to who in the stopped vehicle has the boozy breath, giving "designated drivers" the additional worry that they will be suspected of DUI because of the fumes produced by their inebriated passengers.

The flashlight may also violate the civil rights of drivers.  At present, in California, if the driver is 21 or older, the driver can refuse to blow into the handheld Preliminary Alcohol Screening (PAS) device commonly used to test the breath of suspected drivers alongside the road.  The officer activates the "sniffer" flashlight and extracts air from within the car without even telling the stopped driver what is happening.  Since its introduction,  the PAS flashlight has been hailed by law enforcement agencies and groups such as Mothers Against Drunk Driving (MADD), but has been criticized by individual rights organizations including the American Civil Liberties Union (ACLU) and Drivers Against MADD Methods.

The Virginia-based manufacturer, PAS Systems International, Inc., claims there is no infringement of individual rights:  "The P.A.S., unlike other hand-held breath test devices, collects its sample from in front of the subject's face, in the same way as a police officer may smell a suspect's breath. Therefore it is not a 'test', nor does it constitute a 'search'. Accordingly, there should be no question of a trespass or intrusion into the privacy of the subject."

The courts will no doubt have to decide the issue.