John Ferak

USA TODAY NETWORK-Wisconsin

First of a five-part video series examining Steven Avery's $36 million lawsuit against Manitowoc County.

Sheriff Ken Petersen decided not to conduct any investigation into his agency's botched rape case that mistakenly put Avery in prison for 18 years for a rape he didn't commit.

Name: Kenneth Petersen, Manitowoc County sheriff, 2001-2007; retired after 32 years in the department.

Biography: Manitowoc native; 1967 graduate of Manitowoc Lincoln High School; obtained associate degree in marketing in 1969 from Lake Shore Technical College, bachelor of science in criminal justice in 1988 from Mount Senario College; joined Manitowoc County in May 1975 as a traffic officer.

Role in Avery wrongful conviction: Petersen was the sergeant who wrongly arrested Avery for the July 29, 1985 rape ,which actually was committed by Gregory Allen.

Key moments from Petersen's sworn testimony of Oct. 13, 2005:

On the night of July 29,1985, Sheriff Tom Kocourek ordered Petersen, then a patrol sergeant, to arrest Avery for the brutal attack on Penny Beerntsen.

"As the shift commander, I would have enlisted the help of other patrol officers. I contacted James Froelich and Mike Bushman and then I make a call to Arland Avery to make sure Steve still lived where I thought he lived. And Arland had some concerns so he asked us if we'd meet at his house and talk to him. So we did, and Arland expressed concern that if Steve resisted ... somebody would get hurt and he asked if I would let him come along so that he could try and talk to Steve so that, you know, everything would go smoothly."

Petersen testified he decided there was no need to investigative his agency's role in botching the Avery rape case that put an innocent man in prison for 18 years.

"None of the people that were involved in the case in the investigative part were there."

On how often Petersen's former boss, Sheriff Tom Kocourek, put himself in charge of solving a crime besides the botched Avery rape case.

"There were just a few times, no more than three ... Normally, if I was to compare himself to myself, I wouldn't be involved."

On his meeting with two detectives the day after Avery's DNA exoneration and release from prison.

"I believe both Andy Colborn and James Lenk came to my office and the same time. (Colborn) said when he was working in the jail, he had received a phone call I believe from a detective in Brown County that he had a suspect who said that he had assaulted a person in Manitowoc County and somebody else was in prison. And that's about it. He said he referred it to a detective and heard nothing of it after that."

As the incoming sheriff, Petersen was alerted by Kocourek to a letter being kept in a small safe that helped validate Avery's wrongful rape conviction.

"There was a letter from some inmate from Brown County Correctional I believe that went in there. I don't know who, but he said that Steve (Avery) admitted to the crime, and I know the sheriff had left that when he left office. There's a small safe in his former office that would have had that."

Source sworn testimony: Magne-Script Video Court Reporting