Understanding the motivation behind brutal murder is crucial, not only for investigators looking to make an arrest, but for victims’ families and the public at large. In the aftermath of a seemingly senseless killing, or string of killings, people are often left with one stupefied question: Why?
Beginning Sunday, Aug. 25, at 7 p.m. Oxygen will explore that question with the new original series, “Killer Motive.” From the producers of NBC’s Dateline, and hosted by award-winning journalists Stephanie Gosk and Troy Roberts, each episode will uncover dark and twisted motives — from vengeance to jealousy to greed — that led to gruesome killings.
While the motives behind discrete crimes can be difficult at first to determine, investigators and psychologists generally agree that most often, the “why” can be boiled down to, in essence, three or four possible motivations. They range from jealousy to greed.
Former FBI Profiler Clint Van Zandt said in a 2006 NBC article that, while the most basic, immediate “why” of a murder can often quickly be determined, deeper motivations — what actually pushed the person over the line into violence — are not as easy to parse.
“The ‘whys’ that are hard to answer are the less obvious, the less sensible ones; the ones that prove to be the most difficult for us to understand,” Van Zandt said. “Motive is the reason, the why, sometimes the darkest chapter in the darkest book in the massive library we call the human mind.”
J. Warner Wallace, a veteran homicide detective and co-founder of the Torrance, California, Police Department's cold case unit, who has been featured on Dateline, says that all homicides spring from financial greed, lust or the pursuit of power.
“You might be wondering if there is a fourth category,” Wallace wrote in a 2018 Fox News op-ed. “There isn’t. What about jealousy? What about anger? Ask yourself the question: What is causing the jealousy or anger? There are only three answers to this question, and now you know them.”
Meanwhile, Peter Morrall, an associate professor of health sociology at the University of Leeds, who has published voluminous research on the criminal mind, allows for four possible motives for homicide: lust, love, loathing or loot.
Morrall says that the lust motive is behind someone murdering a romantic rival, as well as “thrill-killers,” who kill for an erotic charge or “sexual payoff; a love-motivated murder would be the mercy killing of a baby with a major deformity, or of a partner with a terminal disease, according to Morrall.
Loathing can be directed toward one individual, a group or a culture or nation, Morrall says, citing the violence between Israelis and Palestinians; killing for loot, meanwhile, could involve going after an inheritance or insurance payout, a robbery, killing for hire or gang warfare.
"But, finding a motive for murder does not go far enough to explain murder," Morrall wrote. "Most people experience lust, love and loathing, and seek 'loot' in the sense of wishing to be free from financial concerns. However, the vast majority of people do not commit murder."
The FBI notes in a published report, after a serial murder symposium, however, that when it comes to serial killers, determining motive can be far more difficult — and may not even be as crucial to the investigation as one might think.
“Serial murder crime scenes can have bizarre features that may cloud the identification of a motive,” according to the FBI document. “The behavior of a serial murderer at crime scenes may evolve throughout the series of crimes and manifest different interactions between an offender and a victim. It is also extremely difficult to identify a single motivation when there is more than one offender involved in the series.”
The FBI went on to note that, even if a motive can be identified, it might not help to identify the actual killer; investigators also warned that pouring too many resources into determining a motive in a serial homicide investigation could possibly “derail the investigation.”
However, the bureau compiled the following, non-inclusive, list of potential motives for serial killers:
Anger, toward a certain subgroup of people or society as a whole.
Criminal enterprise, with the killer benefiting monetarily or in status because of murder done under the blanket of organized crime or drug dealing.
Financial gain, including “black widow” killings, robbery homicides and those involving insurance or welfare fraud.
Ideology, in order to further the goals of a specific person or group; terrorist attacks and some hate crimes would fit the bill.
Power/thrill, in which the killer becomes empowered or aroused when they kill.
Psychosis could include severe mental illness, as well as auditory or visual hallucinations and paranoid or grandiose delusions.
Sexual desires can also be a motivator, and the FBI noted that there need not necessarily be overt sexual contact reflected in the crime scene for this to be a motive.
For a closer look at the motives behind some truly shocking homicide cases, don’t miss “Killer Motive,” premiering Sunday, Aug. 25, at 7 p.m. ET/PT.
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