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This week in Scottsdale and Phoenix, Arizona, four people were fatally shot with the same gun, according to news reports, with potential links to two more. Two victims were female paralegals and two were male professionals in the field of mental health. Dr. Steven Pitt, the first known victim, was a forensic psychiatrist who often commented on high-profile cases such as the JonBenet Ramsey homicide and Phoenix’s Baseline Killer. Pitt was heard arguing with someone just before he was shot, suggesting he knew his killer.
As of this writing, prime suspect Dwight Lamon Jones was cornered in a hotel room, where he took his own life. No motive has yet been stated, aside from the possibility that the shootings are related to his 2011 divorce and psychological evaluation. Links to a couple killed a few hours before his suicide are being investigated.
Social media discussions, along with labels in news reports, show confusion over whether to call this shooter a serial killer, mass murderer or spree killer. It will depend to some extent on whether these four incidents are the only ones linked to him, but the confusion rests partly on shifts in law enforcement concepts.
Similar confusion occurred with Christopher Dorner five years ago. He’d been fired from from the LAPD and he’d penned a lengthy, rambling "manifesto” that described how he’d inflict vengeance for his unfair treatment. Alienated and enraged, he went on a suicide mission of “asymmetrical” violence, with a long grudge list of people to kill. His identity was suspected or known from start to finish, as he murdered four and wounded three before killing himself when cornered.
Dorner's behavior contrasts with that of secretive, predatory serial killers, who generally operate for as long as they can and select their victims at random. So does Jones' behavior. In the past, both would have qualified as spree killers, but things are not that simple now.
During a symposium in 2005, the FBI dropped the classification of “spree killer,” because law enforcement officers thought it had no practical value. The agency published its decision in 2008 here: https://www.fbi.gov/stats-services/publications/serial-murder
“The validity of spree murder as a separate category was discussed at great length. The general definition of spree murder is two or more murders committed by an offender or offenders, without a cooling-off period. According to the definition, the lack of a cooling-off period marks the difference between a spree murder and a serial murder. Central to the discussion was the definitional problems relating to the concept of a cooling-off period. Because it creates arbitrary guidelines, the confusion surrounding this concept led the majority of attendees to advocate disregarding the use of spree murder as a separate category. The designation does not provide any real benefit for use by law enforcement.”
That being said, the FBI is not the only game in town when it comes to understanding the mindset of multicidal killers or evaluating the usefulness of the "spree" designation. Criminological researchers interested in developmental and psychological issues see value in retaining distinct categories to study their differences. Even subtle differences can be important for intervention, prediction, and situation management.
To achieve clarity for my own research and teaching, I've combined several criminological insights to define the various terms as follows:
1) Mass murder is a focused, singular act, occurring in one basic locale, even if the killer travels to loosely related spots (several rooms in a building or several buildings on a block). There are at least four fatalities and the incident has a defined, short-lived time-frame. The recent school shootings offer good examples, as does Stephen Paddock’s rampage in Las Vegas in 2017.
2) A spree killing involves a string of at least three murders in several locations, arising from a key precipitating incident that continues to fuel the motivation to kill. The murders occur fairly close in time, but the time-frame lasts significantly longer than that of a mass murderer and the locations are farther apart. The victims can be targeted or random. The killer’s identity might be known, such as with Dorner, or might remain unknown until caught, as with the Beltway Snipers.
3) Serial murder, according to the FBI’s simplified definition in 2005 (the same document linked above), involves at least two victims in separate incidents. Some criminologists and psychologists add a propensity to kill again, and a few retain the cooling off period between incidents. Ted Bundy and Joseph DeAngelo are examples.
The value in knowing how spree killers operate lies largely in finding clues for identification and for predicting their next move, finding them, and warning potential victims. Punitive anger is a primary motivator.
Probability analysis from other cases suggests that Jones would be keyed up after each shooting and ready for more until he decided he was finished. He might have designated targets, so even before police identified him, they could have alerted anyone with links to the victims to be watchful. (Dorner had targeted not just colleagues against whom he had a grudge but also their families.) Such strategies aren't available with a serial killer who selects victims randomly or with a mass murderer's sudden, focused onslaught.
Although some spree killers do kill randomly, they usually have a mission or goal. They're often angry at a group of people or at an organization. The earliest acts – e.g., the first shootings – can assist with tracking them.
It might not work in every situation, but for some cases, the spree killer category offers enough benefits to encourage criminologists to continue to study them.
