Sgt. Tierney is a police officer in New Jersey.
During the events of Friday the 13th (1980) played by Ronn Carroll
Sgt. Tierney sees Steve Christy and gives him a lift towards Camp Crystal Lake. While they are driving, Sgt. Tierney tells Steve that not only is it bad enough that it is Friday the 13th, but also that there is a full moon. He goes on to tell him that during these times there are more rapes, robberies and homicides. Sgt. Tierney gets a call from dispatch and drops Steve off. Later, Alice wakes up in the hospital and the Doctor orders her to be given some Valium. Sgt. Tierney tells Alice, her parents are on the way and she asks if anyone else is alive. She asks if Jason is still alive and when Sgt. Tierney tells her they didn't find a boy, she says "then he is still there".