Tommy was once a mobster working for an unknown mob where he got the nickname "The Wiesel". Tommy then at some point left the mob he was in to live a normal life, Tommy was known as a former mobster by the civilians of the town he is in. Tommy was then interviewed by P.K. Todd, a well known mystery novel author to learn more about mobsters, Tommy told P.K. about mobsters and later had a friend note the name of a man named Doug Purcell who was with P.K.
When Detectives Briscoe and Green believe that P.K. was shot and Martin Hass was killed in order to gain publicity for her newest novel that was said to be terrible they discovered that she had interviewed Tommy. The detectives got to Tommy and talked to him while a friend of his was pulling his wheelchair. Tommy tells the detectives how he had seen P.K. eight months ago one time. Tommy tells the detectives that he had a book that listed the names of everyone he encountered and says that the name of the man he left with P.K. was Doug Purcell. Tommy then tells the detectives that he would wish to write their names down to which they supposedly tell him their names and he writes them down on his book. (SVU: "Panic")