Lt. Gov. James “Duke” Aiona signed a bill into law today that strengthens the state’s new ignition interlock law aimed at preventing drunken driving.

The law, which was originally passed in 2008 but takes effect in January, requires people arrested for drunken driving to have ignition interlock devices installed in their vehicles. The devices prevent people from driving after drinking alcohol.

The new law signed today eliminates the requirement for probation for second- and third-time offenders because of the potential cost. The new law also makes it a crime to tamper with an ignition interlock device and makes it a petty misdemeanor to refuse to submit to a breath, blood or urine test for alcohol.