Inside the mind of a serial killer: Insights from an FBI profiler

DeLong argues that the defining characteristic of a serial killer is not mental illness in the traditional sense, but a pervasive lack of remorse. She distinguishes between psychosis, where an individual loses touch with reality, and psychopathy, where the offender is fully aware of their actions but incapable of empathy. This emotional detachment allows them to repeat their crimes, often returning to scenes or keeping souvenirs to relive the experience. Many offenders even attempt to convince themselves of their own innocence to cope with the reality of their life sentences.

While childhood trauma, including abuse and neglect, is a common thread in the histories of many killers, DeLong identifies the aftermath of the first murder as the critical turning point. If a killer avoids capture or benefits financially from an initial, perhaps unplanned crime, the success reinforces the behavior. As they evade justice, their confidence grows and their anxiety diminishes, fueling a cycle of repeat violence. Despite the human appearance of these offenders—who often lack the monstrous traits depicted in fiction—DeLong maintains that some individuals are fundamentally beyond rehabilitation. For those who view murder as a manageable risk, she argues that permanent incarceration remains the only viable protection for society.