Yes, you can get a DUI even if you aren't high. If a cop suspects you could be, aka sees your med card at a traffic stop or you are in an accident, they can drug test you. THC can be in your system days to weeks after last use, depending on how often you use it. State law currently allows them to charge you with a DUI, despite no proof of current intoxication.

That said, I've had my card for going on 4 years without an issue.