> By the time an officer asks you to submit to a BAC test, they've already observed enough behavior to make them believe that you may be a danger to others. Th

> By the time an officer asks you to submit to a BAC test, they've already observed enough behavior to make them believe that you may be a danger to others. That's the goal, but cops also sometimes just like to exercise their power and arrest people who don't show signs of impairment. Or use that as an excuse to search the car and try to find a speck of weed. I certainly don't trust an officer to accurately gauge something so nebulous. Hopefully in a few decades we'll all be in self driving vehicles and DUI will be a thing of the past.