Should convicted drunken drivers be forced to pass an alcohol breath test before starting their cars? Should everyone?

For more than 20 years, special breathalyzers – hard-wired to a car’s ignition to prevent the vehicle from starting if alcohol is detected – have been installed under judicial order in the cars of repeat, or especially egregious, alcohol offenders. But in the past few years, six states have passed laws that require the devices, called ignition interlocks, in the cars of everyone convicted of driving under the influence.

Now, several more states, including California, are considering making interlocks mandatory for all offenders. And a group of automakers has launched a major project with the federal government to develop advanced technologies that could someday make alcohol detectors a standard feature in all cars.

Advocates of interlocks, particularly Mothers Against Drunk Driving, say the devices could reduce the nation’s estimated 17,000 annual alcohol-related automotive fatalities and thereby ease the burden that drunken driving places on the nation’s criminal justice system.

Critics, led by the American Beverage Institute and lawyers specializing in DUI defense, contend that ignition interlocks aren’t as effective as claimed and are a burdensome invasion of privacy. The institute represents restaurants such as Outback Steakhouse and Chili’s.

Susan Ferguson, program manager of the Driver Alcohol Detection System for Safety, a five-year, $10-million project funded by the National Highway Traffic Safety Administration and automakers including Toyota Motor Corp. and General Motors Corp., said the research very well could mean alcohol detectors will become a standard option in every car.

To date, Ferguson said, no country has a universal ignition interlock mandate.