SAN DIEGO -- A former Helix High School assistant principal facing a charge of contributing to the delinquency of a minor for giving a female student a ride to a bus station has filed a legal challenge to the misdemeanor count, a prosecutor said Thursday.

Joshua Stepner, 38, was scheduled to be arraigned Thursday at the El Cajon courthouse, but the hearing was put off until a judge can hear the demurrer challenging the legal sufficiency of the criminal complaint.

Stepner was fired Oct. 26, when it was determined that he violated the school's policy that bans employees from having students in their vehicles.

Helix High School recently adopted stricter policies because the school has been marred by controversy involving student-staff relationships. Four former Helix teachers were convicted of sex crimes between December 2006 and September 2008.

Stepner, who was listed on the school's Web site as the 10th grade principal, is accused of giving a ride to the 16-year-old student, who was reportedly having trouble at home and wanted to visit her grandmother in Oregon.

He faces up to a year in jail and a $2,500 fine if convicted.