Namath, the daughter of Hall of Fame quarterback Joe, was nabbed for speeding shortly before 1 a.m., police said.
As the arresting officer approached her car, a silver Mercedes, he smelled something a little funky.
After a quick search, a baggie of weed was found on the driver's side floorboard. Another 200 grams were found in the trunk, as were an opened bottle of rum and 11 bottles of Miller Light.
Namath told police she didn't know the pot was in the trunk.
She was busted for possession of marijuana, intent to sell, and possession of alcohol by a minor.
As of this morning, she was being held on $3,000 bond.
It's been a rough few months for Broadway Joe, who has been locked in battle with a Palm Beach magistrate over his unruly pack of pooches.
Namath is being sued by a UPS driver who claims he was attacked by the gridiron great's three dogs while making a delivery to his Tequesta home.