Dermott Grogan is the deputy inspector and the father of Peggy Grogan, who was raped by Travis Hillsdale.
History[]
After Peggy was raped, Grogan called Chief Tommy McGrath to investigate her rape. McGrath met Grogan at the crime scene where Peggy was being taken into the ambulance. Grogan met McGrath and Benson at the hospital and McGrath told him that they will find the person responsible for his rape. After a suspect was identified, Grogan attended his trial to see justice done for his daughter. (SVU: "One More Tale Of Two Victims")