Clarissa Cervantes, 32, was arrested on the 10 Freeway at 8th Street in Banning over the weekend, according to jail records.
The incident came just weeks after she convinced a judge to dismiss her previous DUI conviction in 2015. She is due back in court next month.
Cervantes is running for the California State Assembly to replace her sister, Assemblymember Sabrina Cervantes.
The city of Riverside is not commenting on her arrest.