I understand why lawmakers would want to enact such measures, and I'm quite familiar with the result of impaired driving of any kind, having represented those accused of such charges in court. However, it should be noted that the drunk driving laws and the campaign for more punitive punishment are not actually targeting those who have caused harm or have taken a substantial step at causing harm, and the statistics behind the portrayals of the problem are frankly misleadingly reported and takes on the characteristics of a moral panic and a boon to law enforcement in circumventing the 4th Amendment. I have no doubt that any additional measures will continue down the same dead-end path.

Firstly, the NHTSA freely defines fatal crashes as "alcohol-related" or "alcohol-involved" if any person, driver or pedestrian or victim in another vehicle had 0.01 BAC or above. It does not mean that the cause of the crash is related to alcohol, only that it is present in a party involved. For non-fatal crashes, the label attaches if the police report indicates a presence of alcohol on the scene, even when no person involved had been tested or was suspected of intoxication. A glossary of definitions can be found here: https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/...

Secondly, the actual numbers of alcohol-related crashes and fatalities are largely estimates imputed by filling in the gaps in the data with values derived from alcohol-involved data that was collected and extrapolated under the assumption that the two populations would have similar distributions of BAC levels when tested, without regard as to considerations as to why BAC data wasn't collected. The imputation is validated by comparing the new imputed statistics to that which is also derived but from an older method with fewer classification categories and not actual recorded data. Methodology: https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/... In any case, the extent of the problem is obfuscated by both a very broad definition and statistically imputed figures based on earlier estimates. While the researchers have pointed out the shortcomings and limitations of the method, the numbers reported to the public and used to justify punitive measures under criminal and administrative laws are taken at face value.

Thirdly, the common DUI/DWI laws punish in a manner more out of the Minority Report than how any criminal justice system that isn't a sham should - by punishing behavior based on the potential for such behavior writ large to potentially cause harm, although there's no victim, no actual harm, no intent to cause harm, and in some cases may not even be possible to cause harm. It's pre-crime in the purist sense, especially since nearly all states have vehicular homicide and vehicular assault charges, or charges that cover the same ground, to deal with instances where actual harm is caused. This is made possible by lawmakers simply designating an arbitrary BAC level as the line for per se intoxication, regardless of actual impairment. NHTSA's own literature states that their guidance material is focused not only determining impairment, but determining whether any individual stopped by the police has a BAC above 0.08, a figure that shifted throughout time and was first set into law around the height of the push for prohibition. Field sobriety tests and such, obviously, have tons of critics both on the false positive and false negative side, but more problematic is the fact that the punitive laws are made not to stop impaired driving but rather, to act as a crude way of divining whether a person's BAC is over or under a precise but arbitrary level, through which probable cause can be established. It's a giant game of charades.

Many laws passed with the best of intentions end up with unforeseen outcomes and ramifications. This is worse than that, as it takes a real problem of unknown scale and pushes it into moral panic territory. Maybe the moral crusaders of MADD should actually take a hint from their organization's name and figure out the extent of the problem outside of crashes where only the driver is killed (70% of alcohol-related fatalities, the NHTSA estimates) before letting loose the moral panic at the heart of their campaign. Reading the footnotes tend to help.