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Law and Crime

Killer Knots

Some serial killers have a distinct preference for binding methods.

K. Ramsland
Source: K. Ramsland

The idea of “signature” behavior while committing a crime is that offenders make choices that reveal aspects of their personality.

“The killer’s signature is his psychological ‘calling card’ that he leaves at each crime scene across a spectrum of several murders,” says former homicide detective Robert Keppel.

It might be a ritual, a wound pattern, or a tool for achieving a goal. Often, it's sexual or anger-driven. I’ve written more broadly about signatures here. This post focuses on knots.

A basic book on tying knots will discuss function, form, and material. You’ll find knots that loop, hitch, join, bind, slip, slide, stop and constrict. There are figure-eights, square knots, sheet bends, a “Highwayman’s Hitch,” and a “Bottle Sling.” Some have several names; some have none. The type of material matters, too, because the person tying the knot wants both security and strength. Sophisticated knots used in murders suggest that the killer practiced them, identified one he liked, and spent enough time with a victim to tie it. He might even have taken some risk to make sure he used it.

Quite a few serial killers crave the feeling of domination they experience with bondage, and some in this category choose a specific type of knot. They might have served in the military where they learned about sophisticated knots, or they might just have taken a basic knot-tying course as a boy. Generally, they’ll use a knot that they believe best serves their goal, but a few introduce a bit of flourish. The more unique or intricate, the more their MO includes a personal stamp or signature. Such behavior, while entertaining for the killers, can also assist with their identification and conviction.

Dennis Rader, the “BTK” killer of Wichita, Kansas, arrested in 2005, was convicted of 10 murders. Having experienced pleasure during childhood games of being bound with rope, he retained this pleasure into adulthood. In Confession of a Serial Killer, he explains his attraction.

“I was helpless,” he said of his boyhood experience, “but it was sexually exciting.” He collected string and twine and learned to tie knots for fishing. Then he became a Boy Scout. “I learned my favorite, the clove hitch, as well as the double half hitch, the square knot, and the bowline knot. As the bondage theme grew, string turned to cord, ropes, straps, leather belts, tape, chains, devices, and plastic. The hangman’s noose excited me later on.”

He used such nooses on himself in autoerotic activities. He also used several different knots to bind victims. The knot to bind Julie Otero was a clove-hitch, but a later murder involved a granny knot. Rader mentioned the clove-hitch again in his "cat-and-mouse" communications with police in 2004, and later referred to it as his “strangler knot.”

The “Golden State Killer,” Joseph DeAngelo, also knew his way around knots. Although not yet tried, he seems to have been responsible for several crime sprees in California, starting with home break-ins around Visalia during the mid-1970s.

He’s also accused of being the East Area Rapist, who terrorized couples. He’d enter a home at night, awaken the couple, and threaten them with a gun. He’d force the woman to bind the man before he’d tie her up. He’d make the man lie on the floor, facedown, and stack dishes on his back. If he moved, the intruder said, the dishes would make a noise and then everyone in the house would die. This offender was also called the Diamond Knot Killer, for the type of decorative knots he used at some scenes, linking the rapist to a murder spree attributed to the Original Night Stalker. DeAngelo was arrested in 2018.

Jack Unterweger, “The Courier,” went to prison for murder in 1976. Over the years, he learned to write well enough to publish poems, plays, and a prison memoir. Some won awards and convinced the literati that art had reformed this killer. Several influential Austrians petitioned for Unterweger’s release. He got early parole in 1990 and acquired gigs as a crime journalist. Sex workers in two countries died. Then he traveled to Los Angeles to write about sex workers there. Three died, strangled with their own bras.

What linked these three victims was a unique knot. Los Angeles criminalist Lynn Herold, an expert on strangulation ligatures, noted the method: the bra was dismantled, with the band stripped from the elastic, always on the left side, and then tied in an identical complex manner. It turned out to match knots used to strangle several European victims that Unterweger was suspected of killing. He was arrested, tried, and convicted of nine counts of murder and sentenced to life without parole. The knot analysis helped to ensure his conviction. Having sworn to never return to prison, Unterweger used the drawstring of his jumpsuit to kill himself – with his signature knot.

After “Dating Game Killer” Rodney Alcala was convicted in California for the murders of four women and a girl, New York officials wanted to show a link between his MO there and two New York-based murders in which Alcala was the chief suspect. They hired former FBI profiler Mark Safarik to make a behavioral analysis.

The victims were all white females that appeared to have been targeted or chosen. All bore blunt force trauma and were strangled manually or with a ligature. Five, including one New York victim, bore bite marks. Five, including the other New York victim, had been transported to another location. In the ligatures of five (including one New York victim), multiple knots had been tied. This behavior, Safarik said, was sufficiently unique to be considered part of a signature. Before Safarik’s analysis could be used in proceedings, Alcala pled guilty to both New York murders.

Research on serial killers has become more sophisticated over the past decade, with a focus on nuanced behaviors. Knowledge about ropes and knots adds a valuable skill to the investigative toolbox.


Keppel, R. D. & Birnes, W. J. (1997). Signature killers: Interpreting the calling cards of the serial murderer. Pocket.

Ramsland, K. (2016). Confession of a serial killer: The untold story of Dennis Rader, the BTK Killer. ForeEdge.

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