Thomas Dolan was an alcoholic in Negative Reaction.
Dolan was drinking in a junkyard when he heard the loud bang of a gunshot go off. He ignored it and attempted to go to sleep when he heard another gunshot. Dolan went to investigate, leading him to find Paul Galesko with a badly shot leg hopping toward him and begging as to where he could find a telephone. When he learned that the case was that of a confrontation over a ransom for Paul's supposedly kidnapped wife, Frances, Dolan was eager to give his sworn statement defending Paul's actions against Al Deschler. Later, after he had sobered up, Dolan was visited by Lieutenant Columbo in a homeless shelter to inquire about the time between the two gunshots, but to the lieutenant's misfortune Dolan had to inform him that due to his drunken state he does not remember any of the events of what transpired with Galesko in the junkyard or even giving his statement to the police.
Thomas Dolan was played by Vito Scotti.