NORRISTOWN, Pa. (CBS) – A Philadelphia woman has admitted in Montgomery County Court to the hit-and-run crash last year that left a Plymouth-Whitemarsh High School senior dead the day after the school’s basketball team won the state championship.

Stephanie Phillips, 20 (above), is facing at least a mandatory year behind bars after pleading guilty to a felony charge of leaving the scene of an accident involving death.

Authorities say Philips struck Denise Cotteta on a rainy Sunday night when the 17-year-old ran into Germantown Pike in front of the high school during a student celebration last March.

Montgomery County prosecutor Rebecca Strubel says Phillips was not charged with homicide.

“This charge is based solely on the fact that the defendant failed to stop at the scene of the accident as required by law, and was in fact pulled over 2½ miles from the accident scene,” Strubel told KYW Newsradio.  “She did realize she struck a pedestrian, she panicked, and she fled.”

Had Phillips stopped, Strubel says, she would not have been criminally charged.

Police say Phillips was not under the influence of drugs or alcohol at the time of the crash.

Reported by Brad Segall, KYW Newsradio 1060.

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