John Ferak

USA TODAY NETWORK-Wisconsin

There was one simple way to avoid the allegations that Steven Avery was framed, say national law enforcement experts, and that was to keep Manitowoc County Sheriff's officers away from the investigation.

Authorities assured the public from the start of the investigation into the murder of Teresa Halbach in early November 2005 that Manitowoc County wouldn't be involved because of a pending $36 million wrongful conviction lawsuit Avery had filed against the county over his mistaken rape conviction in 1985. Calumet County took over the Halbach investigation and prosecution.

"The Manitowoc County Sheriff’s Department’s role in this investigation was to provide resources for us when they were needed,” then-Calumet County Sheriff Jerry Pagel told the media in 2005. “As we needed items on the property to conduct searches, they provided that piece of equipment and that’s their role and their only role in this investigation."

Special prosecutor Ken Kratz echoed Pagel’s remarks, saying “the Manitowoc County Sheriff’s Department and other law enforcement community was very sensitive to any appearance at all of conflict."

In mid-October 2005 — less than a month before Halbach was killed — Avery’s civil lawyers, Walt Kelly and Stephen Glynn, asserted that Avery could have been exonerated eight years earlier than he was if Manitowoc County Sheriff's Sgt. Andrew Colborn hadn't disregarded information a Brown County detective gave him in a 1995 phone call that pointed the finger at another suspect in the 1985 rape. Avery's lawyers also said Lt. James Lenk learned about the call but did nothing.

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Once it was known that Halbach had gone missing, Lenk and Colborn disregarded their obvious conflict of interest, experts said. The detectives volunteered to play an active role in the murder investigation that focused from the outset on Avery, their court testimony reflects. Colborn testified he drove out to the Avery Salvage Yard to interview Avery.

“By acknowledging a conflict right at the start, you have to walk the walk and live by that,” said Gregg McCrary, a prominent retired FBI agent who teaches policing at Marymount University in Arlington, Va. “It’s not just something to say, but something to do. The one overriding issue is the integrity of this investigation. You can’t compromise that. This goes to public perception of law enforcement.”

Lenk testified at Avery’s trial that he never disclosed to Pagel nor to either of the lead investigators, Mark Wiegert of Calumet County and Tom Fassbender of the Wisconsin Division of Criminal Investigation, that Lenk was embroiled in Avery’s eight-figure lawsuit against his employer.

In the days leading up to Avery’s arrest on murder charges, Lenk made Avery's bedroom his obsession, testimony from the Avery trial reflects. Lenk sought to find sufficient evidence to tie Avery to Halbach’s disappearance to secure Avery's arrest. Lenk inspected Avery’s bedroom a handful of times between Nov. 5-8, 2005 — all while the public and press were under the impression Manitowoc County was not gathering evidence against Avery.

“Everybody gets tainted when this goes on,” McCrary said. “Both Manitowoc and Calumet County Sheriff’s Offices are now stained by this. It’s a big problem. They just created this huge problem for themselves for this case. Here, it was unusual to have officers involved in a civil lawsuit also actively investigating the crime, when local authorities announced they would not play a role. Nobody can throw stones or make any allegations if you’re not involved in this case. They opened this door for conspiracy theories themselves."

“Initially, it was quite appropriate for them to recuse themselves from the case,” said Jim Trainum, a nationally recognized crime consultant and former homicide detective in Washington, D.C. “However, it appears they were more interested in the public perception than the reality of it.”

Pagel, who retired as the Calumet sheriff in 2010, did not return messages seeking comment.

TIMELINE: History of the Steven Avery case

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The events of Nov. 8, 2005 were a watershed moment for both the Avery murder investigation and the fate of Avery’s $36 million civil lawsuit against Manitowoc County.

In the days leading up to Nov. 8, Sgt. Bill Tyson of Calumet County acted like a pit bull at the Avery property. He made sure no Manitowoc County officers wandered around the Avery property alone.

But he saw Colborn, Lenk and fellow Manitowoc County detective Dave Remiker at the scene. “It was told to me that no Manitowoc County deputy should be alone on the property,” Tyson later testified.

Tyson was not on duty at the Avery property on Nov. 8. That day, Calumet County deputy Dan Kucharski was assigned to the Avery trailer.

Colborn and Lenk showed up yet again. Kucharski testified that nobody told him Colborn and Lenk were not to be left alone. “I was doing other things. I was taking photographs. I was searching the night stand,” Kucharski testified.

Colborn and Lenk remained preoccupied with Avery's bedroom. When Kucharski turned away, the two Manitowoc County detectives converged near Avery’s bed and a small bookcase. Suddenly, Lenk made a startling discovery.

“Lt. Lenk said something to the effect of, ‘There is a key on the floor here,’” Colborn testified.

The next day, Avery was arrested. By Nov. 11, Kratz declared that Avery would be charged with first-degree intentional homicide. “The key located in the bedroom of Steve Avery’s residence was successfully used in the ignition of the Toyota RAV4 owned by Teresa M. Halbach,” the criminal complaint stated.

The two Manitowoc County detectives had found a critical piece of evidence, and under highly suspicious circumstances. The key contained Avery’s DNA. But the blue lanyard and lone ignition key on a black plastic clasp didn’t contain Halbach’s DNA.

Kucharski testified he previously searched the bedroom carpet and didn’t see the key.

Once Avery was jailed on a murder charge, Avery's $36 million civil lawsuit was effectively ruined. Two of the last remaining depositions, against former sheriff Tom Kocourek, and former prosecutor Denis Vogel, were canceled. While in jail, Avery settled his lawsuit against Manitowoc County for $400,000. Avery’s cut of the settlement was needed to hire top-notch criminal defense lawyers Jerome Buting and Dean Strang.

"It was unusual to have officers involved in civil lawsuits also actively investigating the (Halbach) crime, especially when local authorities announced they would not play a role at all," said Lisa Kern Griffin, a professor at Duke Law School and a former federal prosecutor in Chicago. "It was an extraordinary situation because of the pending lawsuit. There should have been stronger measures in place to make sure the conflict did not impact the investigation or appear to."

USA TODAY NETWORK-Wisconsin made numerous attempts to reach Colborn and Lenk for comment for this story. Colborn did not return multiple phone messages left at his office seeking comment. On Jan. 19, Colborn sent an email to the USA TODAY NETWORK-Wisconsin stating "all these allegations against Mr. Lenk, myself and our agency are totally false. ..."

By March 1, 2006, Calumet County's Wiegert had obtained a spoon-fed confession from Avery’s mentally challenged 16-year-old nephew, Brendan Dassey. On March 1 and 2, police swarmed the Avery Salvage Yard property again. Authorities previously did an intensive eight-day-long search of the property in early November.

Back then, multiple shotgun shells were scattered across the concrete floor of Avery's garage, yet none were found to contain any blood, DNA or trace evidence from the murder victim.

This time, the investigators weren’t just from Calumet County and the Wisconsin Division of Criminal Investigation.

Manitowoc County’s top detective, Lenk, was back on the Avery property, court testimony showed.

This time, bullet fragments and a nearly intact bullet were found. A state crime lab technician later testified that ammunition contained Halbach's DNA.

Lenk and Colborn did not realize their recurring presence at the Avery crime scene would prompt Avery's lawyers, Buting and Strang, to spin a courtroom narrative accusing them of planting blood and manufacturing false evidence, national experts said.

Consider this:

It was the Manitowoc County Sheriff’s Office — not Calumet County — that initially took control of the Avery junkyard and Halbach's Toyota RAV4 at 10:54 a.m. Nov. 5, 2005. This was about 30 minutes after Halbach's cousin, Pamela Sturm, a longtime former private investigator, reported she located the Toyota RAV4 shortly after obtaining permission to search Avery's expansive 40-acre scrapyard, which contained about 3,800 vehicles.

Court documents show Lenk put himself on duty around noon after being made aware of the vehicle's discovery that Saturday.

But his activities and movements cast a shadow of suspicion when he took the stand during Avery's trial. Lenk's behavior was highlighted in last month's blockbuster Netflix documentary, "Making A Murderer."

At a pretrial deposition, Lenk testified he didn't arrive at the Avery property until after dark, probably 6:30 or 7 p.m. At the trial, he testified he arrived closer to 2 p.m. Outside agencies began keeping a log of police officers coming and going around 2:30 p.m. The log shows no entry for Lenk, but showed Lenk, Colborn and Remiker signed out together shortly after 10:40 p.m.

Court documents indicate Calumet County took control of Halbach's SUV from Manitowoc County at about 3:05 p.m. Remiker was one of the first deputies to observe the discovery of Halbach's SUV. He stayed on the property and searched Avery's trailer and detached garage the next day.

Manitowoc County would have had roughly four hours to plant evidence within Halbach's vehicle before Calumet County officially took control of the RAV4 — and possibly many more hours than that if Manitowoc County detectives already knew about the existence of Halbach's SUV before it was officially found.

Colborn arrived at the Avery property shortly after 5 p.m. on Nov. 5, court documents reflect.

Lenk had access to Avery's blood vial that had been stored in a box at the Manitowoc County Courthouse because he wrote a report in 2002 submitting the package to the crime lab in Madison for DNA testing.

After Halbach's vehicle was hauled off the Avery property, a tiny amount of Avery's blood turned up near the key ignition.

Lenk and Colborn's decision to put themselves into the center of the Halbach murder investigation made it easy for Avery's defense lawyers to suspect them of fabricating evidence and planting blood to frame Avery, the experts said.

“Having full knowledge of the lawsuit by Avery against them, they should have avoided participating in the investigation, giving up all authority to another agency,” said James Adcock, a forensic consultant on homicides with the Center for the Resolution of Unresolved Crime, in Memphis, Tenn.

“If that had happened, we would not have seen the two main detectives in the search or for that matter anywhere near the case. I do not feel the detectives planted evidence but their mere presence, while under the lawsuit cloud, gives the appearance of improprieties and that is all that is needed as a conflict of interest,” Adcock said. “Without that appearance, there was no case for the defense.”

At trial, Colborn was forced to explain why he methodically called in the license plate and the model and year of Halbach's vehicle to one of his sheriff's dispatchers on Nov. 3, 2005 while out on road patrol — two days before Halbach's SUV was located.

"Lynn, can you run Sam-William-Henry 582?" Colborn asks.

"OK, it shows she's a missing person. And it lists it to Teresa Halbach."

"OK," Colborn responded.

"That's what your looking for, Andy?"

"Oh, '99 Toyota?" Colborn followed up.

"Yep."

"OK, thank you."

When Halbach's vehicle was discovered two days later, its plates were missing. Police found the plates thrown into another junked vehicle at the Avery property.

"Were you looking at these plates when you called them in?" Strang asked Colborn during the murder trial.

"No, sir," Colborn testified. "... I should not have been and I was not looking at the license plate."

Trainum said Manitowoc County deputies could have remained on the outer perimeter of the Avery property, just like the media or curious spectators gather near a taped-off crime scene.

It would have been acceptable for sheriff's detectives to remain at their offices in downtown Manitowoc to field calls as consultants. They could have given advice to Calumet County including useful background information surrounding Avery, his acquaintances or their knowledge of the Avery Salvage Yard, Trainum said.

By not doing any of that, Colborn and Lenk cast suspicion upon themselves by finding the first significant clue located inside of Avery's bedroom — the Halbach ignition key also containing Avery's DNA within days of Pagel declaring Manitowoc County would not be directly involved.

Furthermore, it was revealed during Avery's trial that Colborn’s written reports of his involvement in the Halbach case were less than a half of a sheet of paper. Colborn chose not to mention in his written reports that he was present when he and Lenk found the spare ignition key under questionable circumstances.

"By them physically being there when there was no reason to be and nothing to contribute at that point, it raises eyebrows," said Trainum, the criminal case review consultant in Washington, D.C. "As cops, we start to look for evidence to confirm our theory rather than evidence to test that theory. That brings so much doubt to me on the verdict itself. They opened the door for that, so shame on them.”

"Making A Murderer" also shows Colborn escorting prisoner Dassey back to the courtroom on the night of jury verdict. As the guilty verdict is being read, Colborn has a front row seat in the courtroom, overlooking Dassey's shoulder. Colborn, who lost in the 2006 election to become Manitowoc County's Sheriff, is now the lieutenant in charge of his agency's detective bureau. He was promoted after Lenk retired a few years ago.

Trainum said the Halbach investigation makes a compelling case study for other police professionals to analyze whether the murder investigation “was done fairly.”

“There’s doubt and a lot of doubt, so how can we learn in the future to prevent this from happening again?” he asked. “Other people allowed these things to happen. Where were both of the sheriffs? Where was the (investigation’s) supervisors? Shame on them. They should have all said, ‘Sorry, guys, I’m not going to let you in.'”

John Ferak: 920-993-7115 or jferak@gannett.com; on Twitter @johnferak