Stephanie Pratt was arrested on suspicion of driving under the influence on early Sunday morning in Hollywood.
"It was your basic DUI. Our traffic officers driving down the street spotted her and pulled her over," Sgt. Sal Ogaz told People Magazine. "She was cooperative and there were no issues with her arrest."
Stephanie spent the Saturday night celebrating Holly Montag's birthday at Empire nightclub and got arrested at 3:45 a.m. and was charged with a misdemeanor.
Pratt tweeted earlier in the evening: "its my sissy @hollymontags bday party! just finished dinner and going to Empire but im pretty tired aka yes i am the party pooper :("