Under new laws, some cars in America will be fitted with ignition interlocks that prevent engines from starting until its driver blows into an alcohol detector.
The new sobriety test will be issued in six states to drivers who have been convicted of driving while drunk.
The law took effect from January 1 for first-time offenders in Alaska, Colorado, Illinois, Nebraska and Washington state and repeat offenders in South Carolina will now be required to prove they are sober via the breathalyser-type gadget.
Mothers Against Drunk Driving (MADD) has been campaigning for the ignition lock law to be introduced across the nation, arguing it could save thousands of lives.
David Malham, of the Illinois chapter of MADD, said: "It's amazingly inconvenient. But the flip side of the inconvenience is death."
Users must pay for the devices, which in Illinois cost $80 (£55) to install on dashboards and $80 a month to rent; there is also a $30 (£20) monthly state fee. The devices also require periodic retesting.
Other states in America with similar laws include New Mexico, Arizona and Louisiana and other state judges can rule that the device be fitted to convicted drunk drivers cars, but MADD said they are rarely ordered unless laws dictate it.
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