The BTK Story
In 1983 two teams of detectives were assigned to reinvestigate the murders. They set out on a cross-country trip, collecting saliva and blood samples from over 200 people that had been flagged by their computer as prime suspects in the case. The samples collected were all voluntary, only five of the men refused. The blood tests ultimately eliminated all but 12 of the names on the list (including the five who refused the tests).
In July of 1984, investigators, set up a task force, nicknamed "The Ghostbusters" and hired a computer consultant to work with them in an attempt to try and discover the identity of BTK. After assembling their massive collection of DNA evidence, seven years after the last murder, investigators finished entering their data into an IBM computer, and a list of suspects began to spew out.
"The Ghostbusters" task force discovered some of the most promising evidence during their investigation. One of the most startling clues was the revelation of one similarity, all of the murders occurred within 3 1/2 miles of one another. This led investigators to believe that the BTK strangler only felt comfortable killing in areas that were familiar to him.
During the fall of 1984, one of the task force investigators took the February 10, 1978 BTK letter to Xerox headquarters in Syracuse, New York. There a lab technician concluded that the letter was a fifth-generation copy of the original, which would make it virtually impossible to trace. In addition, the technician went on to state that the machine used to generate the copy was located at the Wichita State University library.
During the investigation into the letters, the contents of the poems were also regarded as clues. It was soon discovered that the Vian poem was patterned after a "Curly Locks" nursery rhyme that had only just appeared in Games, a puzzle magazine. After making this startling discovery, investigators obtained a list of all the subscribers to the magazine in question.
The Fox poem, titled "Oh Death to Nancy," had been patterned after a poem entitled Oh Death which had been published in a Wichita State University textbook. The book had previously been used in an American folklore class; hence, investigators obtained a copy of the class roster.
Law enforcement officials have not yet released BTK's letters to the public. When asked to typify them, Capt. Paul Dotson stated, "Here I am. Pay attention."
Using all of the available evidence obtained, investigators soon began to assemble lists of every white male that lived within a quarter-mile of the Oteros' house in or around January 1974. Investigators also made similar lists for the Vian, Fox and Bright homes. In addition, task force investigators compiled lists of men living within 1 1/4 miles of each of the victim's homes; they also assembled lists of white male students who attended Wichita state University between 1974 and 1979. The smallest list contained the names of eight people who had checked out the mechanical engineering textbook from the library where the Otero letter was found.
Detectives decided that the most significant of all were the address lists. ''The main crux of our search always was geographical," said Lt. Kenneth Landwehr of the Wichita Police Department. "According to the behavioral scientists, the individual lived close to where he was striking."
Once the lists were completed, investigators used their computer to try to come up with a more precise list of suspects. The computer gave them 225 possible suspects, most of whom no longer resided in Wichita. One by one, the detectives set out to eliminate each of the 225 possible suspects.
One of the key pieces of evidence that the killer left behind was his semen. Lab technicians were able to determine that it was a type of semen found in fewer than 6 percent of all males. Police will not comment as to the type, citing their rules of evidence.