According to this article the girl was attempting to cross over the tracts and there was no crossing near the site where the accident happened. So, it could have simply been an accident and she didn't get across fast enough.
Miss Deaf Texas killed by train
Updated: 3/13/2006 6:22 PM
By: News 8 Austin Staff
Police say the woman hit and killed by a train in South Austin is Miss Deaf Texas.
The accident happened at West Oltorf and Thornton Road about 2:30 p.m. Monday.
Police say 18-year-old Tara McAvoy was walking home at the time. They say she was standing on the west side of the tracks, about 150 yards away from the Oltorf crossing.
The Union Pacific train was traveling northbound. Police say she was trying to cross the tracks.
There is no crossing near the site where the accident happened.
McAvoy graduated from Gallaudet University High School last year in Washington, D.C.
She was named Miss Deaf Texas on June 25, 2005. She was planning to compete in Miss Deaf America this summer.