Denise Piccione, girlfriend of Giovanni Ramirez, was arrested at a hotel in Clark County on Saturday on charges of possession and trafficking of methamphetamine.
She was arraigned on Wednesday but has entered no plea. A preliminary hearing has been scheduled for July 27.
Piccione was charged in Las Vegas with trafficking in controlled substance, approximately 5.6 grams of methamphetamine, possession of controlled substance with intent to sell, and possession of a dangerous weapon, a switchblade knife.
Defense attorneys for Ramirez contend his girlfriend was with him on March 31 when Bryan Stow was brutally beaten and say that the couple never went to Dodger Stadium.
Attorneys say Ramirez and Piccione walked to a nearby motel that day. Videotape might exist from the motel and a nearby gas station, and lawyers argue it would help exonerate Ramirez.
According to witnesses, Stow was beaten by two Dodgers fans who escaped in a car driven by a woman. That woman is not believed to be Ramirez's girlfriend.
Piccione, 26, has been described as a person of interest in the Stow beating case.
The LAPD says Ramirez remains the chief suspect in the Stow beating case, but he has not been charged.
Ramirez is spending 10 months in prison for violating parole.
Stow remains in a San Francisco hospital, recovering from severe brain injuries.