Pick Me Up magazine asked for my professional opinion on John Duffy and David Mulcahy in their regular column ‘Making of a Monster.’ Out in the 15th March 2012 edition, I supplied the following psychological insight:
John Duffy and David Mulcahy, the ‘Thriller Killers,’ were joined together by an obsession with cruelty and crime. This shared obsession was so strong that their rape victims described some kind of psychic understanding between the two men. They would carry out their crimes without speaking a word to one another, but knowing exactly what needed to be done next. One rape victim said of them, “It was two bodies but one brain.”
The bond between the two men was strengthened by their sexual inadequacies. Duffy’s hate of women resulted from a low sperm count which prevented him from impregnating women. Mulcahy, on the other hand, had difficulties maintaining an erection. Both men shared a desire to have control over women, as well as to have control over life and death. This is what drove them to not only rape women, but also torture and humiliate them.
Duffy and Mulcahy were inadequate in many ways, both as children and men. Their shared rage at these inadequacies fuelled their need to exert power and control over women. Armed with their ‘rapist’s kit,’ as they called it, they were motivated by the ‘thrill’ they gained from pure cruelty. It was a deadly mixture of their inadequacies and their friendship that made these men form such an unusual and monstrous alliance.