Ignition interlocks require the driver to blow into a device to detect any alcohol use. If it detects alcohol the engine will not start.
"This little in car probation will make sure you are not driving while you have alcohol in your system," said Laura Dial, the executive director of Mothers Against Drunk Driving in Tennessee.
The organization does support the use of ignition interlock devices.
MADD did not support the Tennessee law in its current form. Leaders feel it does not meet the group's goals.
"Which is to mandate is to mandate ignition interlocks for all convicted DUI offenders," explained Dial.
The Tennessee law does not require the ignition device unless a convicted offender had a blood alcohol content of .15 or higher.
MADD said that high BAC has not proven effective in other states.
"There have not been any states that have a significant reduction in alcohol related fatalities after passing that sort of law and there are a few states that have passed those high BAC laws," said Dial.
According to MADD, after New Mexico and Arizona put all-offender laws in place for anyone convicted of DUI, alcohol-related fatalities dropped by 30 percent.
That type of reduction in Tennessee would prevent approximately 100 alcohol-related fatalities in the Volunteer State.
"That does not even count the number of injuries we could prevent," said Dial.
The ignition locks will also be required if a minor was in your car at the time of the offense; you were involved in an alcohol-related wreck; or you violate the implied consent law.
DUI fines will be increased to cover the cost of installing, monitoring and removing the ignition devices from vehicles.