Lawmakers in Illinois and around the country have been given fact-based evidence from researchers concerning the efficacy of laws that impose ignition interlock devices on the vehicles of convicted drunk drivers. These devices prevent vehicle operation when they detect alcohol in the driver. A study that analyzed more than three decades of national data on alcohol-related traffic fatalities found that these deaths went down the most in states where all people convicted of a DUI offense had to use ignition interlocks.

When the study compared the results to places that only required the intervention for repeat offenders or at a judge’s discretion, mandatory laws emerged as the strongest way to prevent roadway deaths due to impaired driving. States with mandatory laws experienced a 7 percent reduction in these deaths.

To arrive at these conclusions, the researchers looked at data from 1982 to 2013. They evaluated the changes in traffic fatalities as states added laws that required or recommended ignition interlocks as penalties. They applied statistics from the National Highway Traffic Safety Administration’s Fatality Analysis Reporting System when calculating the effects of the laws.

A person arrested for drunk driving could be confronted by many potential penalties, including high fines and incarceration. An attorney could explain the possible consequences of a conviction and then construct a strategy to defend against the allegation. Counsel could examine the traffic stop itself to see if the authorities had the required reasonable suspicion to initiate it. Other challenges could be mounted, such as to the way that the sobriety tests were conducted.