A pair of Chinese students has invented a prototype fingerprint scanner that detects whether a driver is legally drunk or is designated to drive the vehicle.

When a driver places a middle finger into the scanner, the device determines if the grooves in a fingerprint match those of people authorized to drive the vehicle and also analyzes the chemical properties of oils and sweat from the digit within 20 seconds. If the driver doesn't pass the test, the engine locks out.

Zhao Wencai and Li Zhoumu from China's University of Geosciences debuted the device at Beijing's third-annual China-International Road Safety Expo. The event has grown, along with concern over driving safety in the country, where there are about 250,000 traffic accidents a year and more than 50,000 deaths caused by drunk driving.

Wired.com suggests that the government require domestic automakers to add a feature like this to all their vehicles as part of a bailout since, according to the Centers for Disease Control, 36 people die in the U.S each day from alcohol-related accidents and the monetary toll of crashes tops $51 billion annually.