Police in Barrington, Illinois confirm Kristin's mom -- Judith Spies (that's her mug shot above) -- was pulled over at a DUI checkpoint at 2:15 AM late last month. Law enforcement sources tell us Kristin was riding shotgun at the time.
Judith was arrested for DUI. Police say her car was impounded since Kristin admitted being drunk and couldn't drive.
We're told Kristin did not play the "do you know who I am?" card ... impressive since she's rumored to be dating Chicago Bears QB Jay Cutler -- and we know how much Chicago loves Da Bears.
Kristen's rep had no comment.
Credit: TMZ