Serial killers, defined by the National Institute of Justice, are those who have committed two or more murders and often with a psychological motive and a sadistic sexual component. Many of our most famous serial killers--Ted Bundy, John Wayne Gacy, and David “Son of Sam” Berkowitz-- are from the 1970s and ’80s. Since then, data suggest, the number of serial killers has plunged, falling 85 percent in three decades.

According to the FBI, now, serial killers account for fewer than 1 percent of killings. This decline in serial killers is said to be due to several reasons such as longer prison sentences, a reduction in parole, better forensic science, and less candy from strangers.

However, as the number of serial killings has supposedly fallen, so too has the rate of murder cases cleared. The U.S. homicide clearance rate dropped from 91 percent in 1965 to 61.6 percent in 2017, one of the lowest rates in the Western world. In other words, about 40 percent of the time, murderers get away with murder.

Thomas Hargrove, the founder of the Murder Accountability Project, a nonprofit that compiles data on homicide, estimates at least 2 percent of the unsolved murders are committed by serial offenders using DNA evidence-translating to about 2,100 unidentified serial killers. Michael Arntfield, a retired police detective and the author of 12 books on serial murder, agrees that the FBI’s projections are off due to patchy data and estimates the number of active serial killers to be 3,000 or 4,000.

Why aren’t more killers getting caught? Arntfield attributes the decline in clearance rate to increased expertise in staging murder, limited investigative resources, growing social isolation in victims, and suspects’ geographic mobility. The modern serial killers learned how to throw the police off their scent with false evidence and careful planning. For instance, the FBI Highway Serial Killings Initiative has investigated 750 murders on highways and identified up to 450 potential suspects, mainly truck drivers well positioned to evade detection. Victims of these crimes are primarily women living high-risk lifestyles who are frequently picked up at truck stops or service stations, which makes it more difficult to connect the dots. “The more locations you’re operating in,” Arntfield explained, “the more difficult it is for law enforcement to see a link.”

Though homicidal maniacs lurk in all kinds of professions, truckers, police personnel, forestry workers, hotel porters, and warehouse managers are found to be the top serial killer jobs. It’s not about the people in these jobs, but the job itself--whether it allows killing on the side. So the lesson is: Don’t hitchhike from sketchy truckers.

<Christina Peng/Arnold O. Beckman High School 10th grade>