Interlocks: The New Prohibition
The BAC threshold for a driver to be considered legally “drunk” is already quite low. In fact, scientists have found that driving while talking on a hands free cell phone is more dangerous than driving at the 0.08 legal limit.
It takes as little as two 6-ounce glasses of wine over a two hour period for a 120-pound woman to reach 0.08 BAC. But the average BAC of a drunk driver involved in a fatal crash is 0.19—more than twice the legal limit.
Currently, interlocks are calibrated at around 0.02 blood alcohol concentration (BAC). If interlocks become mandatory equipment in all cars, they will be set far below the legal limit of 0.08 — most likely at 0.03-0.04.
Here’s why:
- States with Low Legal Limits
Many states have “presumptive” intoxication limits of 0.04 and 0.05, so in those states, the interlocks would have to be set just below those levels. Since car manufacturers must build vehicles that may be driven in all 50 states, these lowest BAC thresholds will have to be the standard for universal interlocks. - Liability Concerns
Because a person’s BAC can continue to rise after he or she stops drinking, interlock manufacturers will have to set the limit lower than 0.08 for their own protection. If the device allows a car to start and the driver crashes while driving over the legal limit, the interlock manufacturer could be held liable. Manufacturers will have to set the devices lower to protect themselves. - Incremental Steps
Activist groups like MADD have a long history of utilizing incremental steps to achieve their goals. For instance, the legal BAC limit has crept down incrementally since its inception. In 1998, MADD successfully pushed for federal highway funding sanctions for the handful of states that had not yet lowered their BAC limits from 0.10 to 0.08. Already, many European countries set their legal limit at 0.05.
- The Federal Government’s Take
The federal government has clearly stated ignition interlock devices should be set lower than 0.08. According to NHTSA’s 2007 Report to Congress on the development of universal technology:
BAC threshold: Current interlocks are intended to prevent driving after any drinking and are set at a BAC of .02 or .025. Non-offender drivers may be unwilling to accept interlocks set at these levels... An interlock set at 0.08 would not guarantee that a driver who is able to start the car is necessarily below the legal 0.08 limit because of the instrument’s potential measurement error.[1]
Find out more about “potential measurement error”.
In fact, Sue Ferguson, Program Manager of DADSS recently admitted this: in-car alcohol-sensors will be set below the legal limit.[2]
When interlocks become universal, the debate over BAC limits will be moot. Technology—not democracy—would decide.
The hidden agenda behind universal interlocks is not to eliminate drunk driving, but to end any drinking before driving. This intrusive technology would treat a couple who enjoyed wine with dinner the same as an alcoholic who just finished his eighth drink. Right now the law recognizes the difference, but soon your car may not.
