Alaska, Colorado, Illinois, Nebraska and Washington state began Jan. 1 requiring the devices
for all motorists convicted of first-time drunken driving. (See
article on Illinois law.) South Carolina began Thursday requiring them for repeat offenders.
Mothers Against Drunk Driving has been conducting a nationwide campaign to mandate ignition locks for anyone convicted of drunken driving, claiming doing so would save thousands of lives. But critics say interlocks could lead to measures that restrict alcohol policies too much.
Users must pay for the fist-sized devices, which in Illinois cost around $80 to install on dashboards and $80 a month to rent; there's also a $30 monthly state fee. They also require periodic retesting while the car is running.
"It's amazingly inconvenient," said David Malham, of the Illinois chapter of MADD. "But the flip side of the inconvenience is death."
Other states with similar laws include New Mexico, Arizona and Louisiana. Most other states give judges the option of forcing convicted drunk drivers to use the devices. In practice though, they are rarely ordered unless laws mandate them, according to MADD.
Until now, that's been true in Illinois, said MADD national CEO Chuck Hurley.
"Illinois has excellent law enforcement," he said. "But the judicial system leaks like a sieve. This law will change the catch and release system to one where people are at least caught and tagged."
In Illinois, the interlocks are mandated only for the five to 11 months licenses are suspended with a first DUI. Drivers can opt not to install them, but then would be banned from driving at all during the suspension period.
Motorists in Colorado get a similar choice -- install the devices or get a longer suspension.
The law taking effect in Washington state actually relaxes penalties on drunk drivers, allowing them to avoid a previously mandatory license suspension by getting an interlock. The bill's author, Rep. Roger Goodman, said too many motorists were driving with suspended licenses.
Motorists could try skirt the devices by, say, having someone else blow into detector or driving someone else's car. But if caught trying to circumvent the interlocks, they could go to jail.
Within a year, up to 30,000 first-time offenders in Illinois could be using them, state officials estimate.
New Mexico was the first state to mandate the devices in 2005. Since then, according to MADD, that state has seen its drunk-driving deaths fall 20 percent.
Hurley said other states could see the same percentage decline within a few years.
DUI deaths nationally have plummeted to around 15,000 from around 30,000 annually in the early 1980s.
Malham, who supports the technology, said in the future even more advanced technology will enable cars to effectively sniff car cabins, scan faces and eyes of drivers or even test sweat on steering wheels to assess sobriety before engines start.
Not everyone is as enthusiastic.
One of the staunchest critics of interlock laws for first-time offenders is the Washington, D.C.-based American Beverage Institute, a trade association representing restaurants and retailers.