The 23-year-old University of Montana graduate student had been pulled over Jan. 3 and refused to submit to alcohol screening, breath or blood tests. Her license was seized and suspended.
The Bozeman Daily Chronicle reported Wednesday that Hepner has pleaded not guilty. She is also fighting the license suspension.
Her lawyer says her requests to speak with an attorney during the traffic stop were denied.
The lawyer says Hepner was allowed to participate in the Miss America pageant Jan. 24, but her Miss Montana duties were suspended Feb. 16.
The Miss America Organization says Hepner will retain her tiara until the next Miss Montana is crowned June 20.