Alison Michelle Ernst, 36, read documents, talked to her lawyer and sat on the edge of her seat as she waited for her initial appearance before U.S. Magistrate Judge Steven Logan in Phoenix.
Ernst, wearing a turquoise-colored hooded jacket and jeans, was arrested late Monday after federal prosecutors in Las Vegas filed charges Sunday accusing her of trespassing and violence against a person.
The federal charges increase the possible consequences for Ernst if she is convicted of throwing a shoe at the former secretary of state.
The judge appointed attorney Maria Weidner to represent Ernst and ordered Ernst detained pending proceedings in Las Vegas.
Outside court, Weidner said Ernst looked forward to resolving the case against her.
Ernst had been arrested in Las Vegas after questioning by the U.S. Secret Service on a local misdemeanor disorderly conduct charge carrying a possible six-month sentence in county jail. She was released by Las Vegas police with a June 24 court date in Las Vegas. Those charges weren't immediately filed.
The federal misdemeanor charges accuse Ernst of bypassing security to enter the ballroom where Clinton was speaking and committing a violent act by throwing the shoe.
The shoe missed Clinton, and Ernst surrendered to authorities immediately after the incident Thursday at the Mandalay Bay resort.
If Ernst is convicted of both federal charges, she could face up to two years in federal prison and the possibility that federal authorities would be able to monitor her movements under terms of supervised release.
Ken Ritter reported from Las Vegas and can be reached at http://twitter.com/krttr .
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