The head of the BTK task force offered details Thursday about the extraordinarily tight-lipped operation.
In a rare interview, police Lt. Ken Landwehr talked with The Eagle about how police were prepared to trace every Jeep Cherokee in Sedgwick County and about how police kept the investigation secret.
Landwehr gave these details:
After a dark-colored Jeep Cherokee was linked to the killer through a North Woodlawn Home Depot store videotape, police made plans to track down 2,500 Cherokees registered in the county.
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The videotape showed the killer leaving a package in a pickup bed in the parking lot, then driving away in the Cherokee.
Police planned to prioritize the Jeep tracing according to the age of the owner, based on the likely age range for BTK, Landwehr said. But investigators knew that BTK could have been borrowing the Jeep, so they were determined to contact every owner.
"We would have finally got through all of them," Landwehr said.
Before that task was completed, however, investigators received a computer diskette from BTK and traced it to Dennis Rader, a 60-year-old Park City compliance officer.
When they drove by Rader's house, they saw a dark-colored Jeep Cherokee. It belonged to Rader's son, who was away on military duty.
After his arrest on Feb. 25, Rader confessed; he pleaded guilty to 10 counts of murder on June 27.
Part of the challenge of protecting the investigation was making sure information leaks didn't occur. According to a task force operations plan released July 8, one police supervisor had the assignment of investigating any leaks.
Landwehr said he didn't know of any significant leaks, and police Capt. Randy Landen, who had some oversight of the task force, said there was "nothing that warranted an investigation."
On Feb. 8, 17 days before Rader's arrest, the investigative task force, including Wichita police and agents with the FBI and Kansas Bureau of Investigation, moved all operations across the street from City Hall to the Epic Center.
Their facilities there, secured by alarms and motion detectors, suited the task force partly because investigators could come and go without being noticed, Landwehr said. There also was plenty of space, and the downtown location was convenient.
There had been reports that BTK used a communication to threaten Landwehr during the investigation. Part of Landwehr's assignment at carefully orchestrated news conferences about the case was to speak directly to the killer.
One communication mentioned Landwehr by name. But Landwehr said he never felt targeted by the taunting killer.
"I never took anything as a threat."
Because Rader had an administration of justice degree from Wichita State University, there was a persistent rumor that he had once applied to be a Wichita police officer.
Landwehr said investigators searched city employment records but found no record of Rader ever seeking a Wichita police job.
"He told us he never applied to the PD. He never applied to any police department."