Power
The reason that Charles Cullen, the man at the center of this true story, is a nurse who murders is to capitalize on the irony that nurses are often caring and life-saving. Just as being a man in the female-dominated world of nursing made him an outlier, so he is an outlier in his motivation for using the special benefit that comes with being a nurse to commit murder. Motivation is all about power. Becoming a nurse granted Cullen access to weapons of murder denied to everyone else. For that matter, Cullen being a male working amongst women gave him a perception of physical power. Terrorizing his wife to the point of restraining orders and divorce was a means for Cullen to feel powerful. Aside from the act of murder itself, probably nothing made him feel more powerful than becoming a serial killer committing a string of murders that most people didn’t even know were homicides.
Corruption
Perhaps, the most satisfying sense of power for Cullen came from realizing that there were people who recognized homicides were being committed but covered it up. In addition to being a story about a specific psychopath, this is also a story of systemic corruption by countless others whose actions facilitated Cullen. By the second page of the book, the reader learns that Cullen had been the subject of countless official complaints, had received multiple disciplinary citations, come under the scrutiny of four law enforcement investigations, was the subject of restraining orders, and had made multiple attempts to commit suicide. Despite these red flags, he somehow still managed to always find a new job as a nurse after losing his previous job. If this collective failure were merely the result of incompetence that would be bad enough, but the truth is more horrific. Especially within the care health industry, decisions were made and actions taken specifically designed to cover Cullen’s trail. Not out of any desire to protect Cullen, but in order to cover up the incompetence of the institutions involved and protect themselves against potential liability.
Lies
Cullen almost gleefully agrees to several polygraph examinations over the course of his life. The quick agreement to requests results from the fact that he has quite specific experience in knowing exactly how the machines work from a biological perspective. He need not concern himself with the psychology of lie detection such as convincing himself that a lie is truth because he knows exactly how to manipulate the machine's measurement of physical changes such as pulse and respiration. He consistently beats the polygraph by lying and having it produce a report indicating he passed with flying colors. Although not allowed as evidence in a trial, police tend to make enormously important decisions about suspects based on polygraph results.
Equally true is that that they lend great weight to criminal profiling. The problem with this dependence is that it is subject to lies of another sort. An FBI profiler admits that most nurses who kill—regardless of the motive—are female and that, in fact, the Bureau had never come across anyone who fit the profile of Cullen before. The basis for investigating any serial killing by a nurse, therefore, is already steeped in the firm belief among investigators in the lie that killer nurses are not male. Furthermore, if deviance does occur, it will certainly not be a heterosexual male with a wife and children like Cullen. Trust in the mechanisms of law enforcement capable of producing lies that delay or obstruct investigations also served to unnecessarily lengthen Cullen’s reign of terror.
