John Ferak

USA TODAY NETWORK-Wisconsin

The Manitowoc County Sheriff's Office could have avoided worldwide scrutiny in the wake of the "Making a Murderer" series if it had just stayed away from the Avery Salvage Yard in November 2005.

But sheriff's officials never steered clear even though Manitowoc County was tangled up in a messy $36 million civil rights lawsuit that seemed destined to make Steven Avery, then 43, a multi-millionaire. Sheriff Ken Petersen's mentor, retired Sheriff Tom Kocourek, was being accused of framing Avery for a beachfront rape that had cost Avery 18 years of freedom.

USA TODAY NETWORK-Wisconsin's extensive review of court transcripts and the investigative case file compiled by the Calumet County Sheriff's Department shows that Manitowoc County played a major role in gathering evidence at the Avery Salvage Yard despite the lawsuit. That potential conflict of interest is a theme that has emerged in the wake of the Netflix docu-series that has drawn wide interest and has brought heavy criticism on Manitowoc County investigators from those who question the validity of the convictions of Avery and his nephew, Brendan Dassey, in the killing of Teresa Halbach.

On July 29, 1985, Petersen, working on the investigation into the rape of Penny Beerntsen, entered Avery's residence and stated, "You're under arrest for suspicion of attempted murder," records show. Besides Petersen, another Manitowoc County deputy who converged on Avery's residence to carry out what proved to be a wrongful arrest was Deputy Mike Bushman.

Fast forward 20 years.

The missing persons investigation surrounding Halbach was in danger of reaching an impasse. Bushman, who had retired earlier that year and was now considered a part-time reserve deputy, showed up at the police command center on the morning of Nov. 7, 2005, eager to prove Avery killed the missing freelance photographer from the Hilbert area.

Even though there was no shortage of police officers from other agencies — agencies not connected to the Avery lawsuit — at Avery Salvage that day, that didn't deter Manitowoc County from sending a large contingent of its own deputies: Lt. Detective Jim Lenk at 7:15 a.m., Sgt. Andrew Colborn at 7:16 a.m., Detective Dennis Jacobs at 7:16 a.m., Bushman at 7:38 a.m., Lt. Todd Hermann at 7:38 a.m.,

Sgt. Jason Jost at 7:45 a.m., Deputy Dave Siders at 7:45 a.m. and Sgt. Scott Senglaub at 7:54 a.m.

Bushman agreed to lead a four-member evidence search party consisting of fellow Manitowoc County sheriff's officials.

It wasn't long before Bushman's team made a fortuitous discovery as they canvassed the northern edge of the Avery Salvage Yard near an open cornfield. "I came across a burning barrel, which was in my section of searching," Siders would testify.

It was Steven Avery's burn barrel not far from his trailer. Siders put his hands into the burn barrel and he removed a heavy metal tire rim.

"I saw a lot of ashes and I saw a lot of burnt, melted plastic parts," Siders would testify. "It appeared to be parts of a cell phone that were actually melted inside the burning barrel."

Remnants of a Motorola emblem for a cell phone and debris from a camera were identified. Authorities believed the charred debris was Halbach's camera and cell phone.

Despite the burn barrel's mid-morning recovery, Manitowoc County Sheriff's deputies would steer clear of inspecting Avery's burn pit area, which was roughly 20 yards from his bedroom window.

Around 4:35 p.m., the sun went down. Another full day had passed without any discovery of Halbach.

The next day, Tuesday, Nov. 8, Avery Road was again swarming with police — Wisconsin State Patrol, Calumet County Sheriff's Office, Wisconsin Division of Criminal Investigation, Two Rivers Police Department, Kaukauna Police Department.

The Manitowoc County Sheriff's Office continued to play a role. At least a dozen sheriff's officials came out to the Avery property that day, logs reflect. Among them: Deputy Inspector Gregg Schetter at 6:40 a.m. and Sgt. Jason Orth at 6:55 a.m. Lenk and Colborn checked in together at 7:20 a.m., followed by Detective Dennis Jacobs at 7:25 a.m. and Lt. Todd Hermann at 7:27 a.m. Although Bushman didn't return, the rest of his search party returned. Senglaub at 7:52 a.m. Siders at 8:02 a.m. Jost at 8:56 a.m. Todd Hermann's older brother, Under-sheriff Rob Hermann, arrived at 11:17 a.m.

The most important clue in the Halbach investigation surfaced shortly after 1:30 p.m. Once again, the evidence was found by a Manitowoc County sheriff's deputy.

Out at Avery's burn pit, Sgt. Jost pointed out a large piece of bone believed to be a spinal column and also a smaller bone that was gray in color. "It did not appear as if anybody had previously dug into or moved anything from within the pile," stated Calumet County Lt. Kelly Sippel. "The two items we observed were lying directly on top."

Jost did not take photographs of his discovery, case files reviewed by the USA TODAY NETWORK-Wisconsin show. Just days earlier, Manitowoc County Detective Dave Remiker and Calumet County Deputy Dan Kucharski were by the same burn pit. They said that they shied away from the burn pit after seeing Avery's barking German shepherd chained up nearby.

Jost and Wisconsin DCI agent Tom Sturdivant chose not to have photographs or video footage showing the purported burial site containing Halbach's remains.

Eight months later, after Avery was charged with murder, Wisconsin DCI special agent Tom Fassbender wrote an email to John Ertl, a Wisconsin State Crime Lab forensic scientist, asking why no photos were taken of the human bones identified as Halbach.

"We typically do not take photos to document a scene if the scene has knowingly been altered," Ertl responded. "In regard to the burn pit, our involvement began with a request to use our sifting equipment. The scene had been obviously altered at that point."

That afternoon, the bone removal was mostly handled by Jost and Sturdivant rather than Ertl's team of trained state crime lab personnel from Madison.

What's more, authorities at the Avery Salvage police command center chose not to call in a forensic pathologist or a forensic anthropologist, records show.

Manitowoc County Coroner Deb Kakatsch first learned about the discovery while watching the nightly television news.

At Avery's 2007 murder trial, lawyers Dean Strang and Jerry Buting called Kakatsch to the witness stand. They wanted her to inform the jury that the lead investigator, Mark Wiegert, along with Sheriff Ken Petersen and two other top public officials from Manitowoc County, the county executive and the corporation counsel, ordered her to stay away from the Avery Salvage Yard after hearing that human bones were discovered by Jost.

Trial testimony showed that about 60 percent of the human bones were never found and additional charred human bones had been discovered about a quarter mile away at the Michels Materials quarry, reports show.

"And, unlike the Sheriff's Department, neither Ms. Kakatsch nor the office of coroner, nor anyone in the coroner's office, had any prior involvement in Steven Avery's civil lawsuit," Strang informed the judge. "And yet her office alone apparently among Manitowoc County law enforcement offices was walled off entirely from performing legal duties, lawful duties, in connection with discovery of human remains."

In the end, Manitowoc County Circuit Judge Patrick Willis ruled that the jury would not hear any testimony from Kakatsch.

"I think it has much more potential to mislead the jury, and I don't see how anything the coroner would have done would have somehow contributed to a less biased investigation in this matter," Willis pronounced.

She was subsequently excused from the courtroom.

Here's a more in-depth examination of crucial evidence used to convict Avery — most of it was evidence the Manitowoc County Sheriff's Office found that has raised conflict of interest questions due to the then-pending lawsuit.

1. Halbach's 1999 turquoise RAV4

Found: Nov. 5, 2005, recovered by Manitowoc County Sheriff's Office.

Key personnel: Sgt. Jason Orth, Detective Dave Remiker and Lt. Todd Hermann

Circumstances: Pamela Sturm, a cousin of Halbach, notified Calumet County that she found Halbach's vehicle on the Avery Salvage Yard property. Manitowoc County rushed to the scene and retained control of the RAV4 for four hours. Detective Remiker testified that the VIN matched Halbach's vehicle. At Avery's trial, Lenk denied he had planted Avery's blood in the front of the vehicle.

2. Leg restraints and handcuffs, novelty sex toys from Intimate Treasures

Found: Nov. 5, 2005, recovered by Manitowoc County Sheriff's Office

Key personnel: Colborn, Lenk, Remiker and Calumet County Sgt. Bill Tyson

Circumstances: During an evidence search that lasted 2½ hours, Colborn found the sex toys in Avery's small bedroom and had them confiscated as evidence. "I stopped what I was doing. I informed Sergeant Tyson, hey, I found some leg irons and handcuffs in here," Colborn later testified. There was no evidence presented that the restraints were ever used to restrain Halbach, but special prosecutor Ken Kratz convinced a jury otherwise.

3. Remnants of cell phone, digital camera

Found: Nov. 7, 2005, recovered by Manitowoc County

Key personnel: Deputy Dave Siders, Retired Deputy Inspector Mike Bushman, Sgt. Jason Jost, Sgt. Scott Senglaub,

Circumstances: Bushman, a retired deputy who helped arrest Avery for the July 1985 Penny Beerntsen rape, led Search Group A, consisting of the four Manitowoc County Sheriff's deputies. It wasn't long before Siders came upon a burn barrel belonging to Steven Avery. He removed a tire rim. Remnants of a charred cell phone and camera debris were collected and used as evidence to convict Avery.

4. Wisconsin license plates SWH 582.

Found: Nov. 8, 2005, the fourth day of Manitowoc County's presence at Avery Salvage.

Key personnel: William Brandes Jr., member of the Brillion Volunteer Fire Department

Circumstances: Shortly after 9 a.m., a volunteer firefighter recovered Halbach's license plates folded up inside the backseat area of a junked station wagon along the northern edge of the Avery property not far from Avery's trailer. Two days earlier, a team of volunteer firefighters had no luck finding the plates during a search of the scrapyard. Volunteer firefighters were recalled not the next day but two days later after Lenk and Colborn inspected additional vehicles. The vehicle containing Halbach's plates had no windows.

5. Spare ignition key for Halbach's RAV 4

Found: Nov. 8, 2005, fourth continuous day of Manitowoc County's presence at Avery Salvage

Key personnel: Detective Lt. James Lenk, Sgt. Andrew Colborn, Calumet County Deputy Dan Kucharski

Circumstances: As Kucharski was sitting on Avery's bed, Lenk spotted a spare key on the floor near Avery's bed. "I believe I said to myself, damn, how did I miss that?" Colborn would testify. Three days earlier, Lenk, Colborn and Remiker searched the room for 2½ hours in front of Sgt. Bill Tyson and the key wasn't seen. The spare key was found to contain Avery's DNA but not Halbach's DNA. Halbach's regular set of keys were never found.

6. Human bones at Avery burn pit

Found: Nov. 8, 2005.

Key personnel: Sgt. Jason Jost of the Manitowoc County Sheriff's Office, Calumet County Lt. Kelly Sippel, Wisconsin DCI investigator Tom Sturdivant

Circumstances: In mid-afternoon, Jost alerted Sippel to his discovery of human bones in the burn pit not far from Avery's red garage and trailer. "Sgt. Jost indicated to me there had been a large burned area behind the red garage on the Avery property located in the northwest corner of the property. He felt that this area may not have gotten searched properly based on the fact that there was a large German shephard in the immediate area," Sippel stated. Jost and others would take no photos showing the locations of where the bones, later identified as Halbach, were located. .

7. Human bones in burn barrel on Barb Janda's property

Found: Nov. 6, 2005, the second consecutive day of Manitowoc County's presence at Avery Salvage

Key personnel: Calumet County's Dan Kucharski, Manitowoc County's Remiker, Lenk and Colborn. The four seized control of four separate burn barrels located on the property. It was later revealed that both animal parts and human bones had been discarded into one of these barrels, which was on the property of Barb Janda and her sons.

Circumstances: Avery's lawyers Dean Strang and Jerry Buting argued that the discovery of human bones in the 55-gallon burn barrel on Steven Avery's sister's property about 150 feet away from Avery's trailer contradicted the prosecutor's theory that Avery burned Halbach's dead body in the burn pit outside his bedroom window. "If Mr. Avery wanted to get rid of the bones from his burn area, he would not put a scattered few in someone else's burn barrel and leave all the rest behind," Strang argued. "That's not making sense. It doesn't make sense. No one would do that."

8. Digital answering machine, Barbara Janda's residence,

Found: Nov. 6, 2005, the second consecutive day of Manitowoc County's presence at Avery Salvage

Key personnel: Remiker

Circumstances: That message helped establish Manitowoc County's belief that Avery had killed Halbach on the afternoon of Oct. 31, 2005. The answering machine message began by saying, "Hello. This is Teresa with Auto Trader Magazine. I'm the photographer and just giving you a call to let you know that I could come out there today, um, in the afternoon. It will probably be around 2 p.m. or longer ..."

9. Bullet fragments in Avery's red garage found to contain Halbach's DNA

Found: March 1-2, 2006,

Key personnel: Remiker, Wisconsin DCI agent Kevin Heimerl

Circumstances: Four months after Avery's arrest, special prosecutor Ken Kratz announced the arrest of Avery's teenage nephew, Brendan Dassey, as a co-conspirator. Avery's garage then becomes the focal point of a secondary search. Remiker and Lenk were back on the Avery property. The garage had underwent numerous searches back in November. Remiker testified, "We found some additional shell casings. We were searching on our hands and knees. At one point I remember DCI Agent Kevin Heimerl located what looked to be a bullet fragment near the air compressor, kind of in the back left corner or the garage. ... My job was to specifically collect that item and make sure it was collected properly."

Lenk testified he did not plant the bullet fragments inside Avery's garage and never stepped inside the garage during the March 1-2, 2006, followup search. "I came back to see if they needed any, uh, food, any assistance with supplies, see if I could help out," Lenk testified. Halbach's DNA was later found on the bullet fragments.

10. Shotgun, rifle confiscated from Avery's bedroom

Found: Nov. 6, 2005

Key personnel: Calumet County's Dan Kucharski, Lenk, Colborn and Remiker.

Circumstances: A Glenfield Model 60 semi-automatic rifle hung on a gun rack above Avery's headboard. A .50-caliber muzzleloading rifle was also confiscated. It contained a piece of masking tape with the name "STEVE" on it. On Nov. 9, Avery was arrested for being a felon in possession of a firearm. Within days, he was also charged with first-degree intentional homicide. Kratz argued that Avery used these weapons to shoot Halbach inside the garage.

11. Photo memory card

Found: Nov. 5, 2005, first day of Manitowoc County's presence at Avery Salvage Yard

Key personnel: Sgt. Jason Orth, Detective Dave Remiker

Circumstances: Orth and Remiker were two of the first Manitowoc County Sheriff's deputies to take control of the blue RAV4. They saw a memory card for a digital camera. It was an important clue to cement Manitowoc County's theory that Halbach was murdered during her work for Auto Trader Magazine. "I remember seeing the letters TERTHERES, looked like Teresa or Terese written on it. I looked under the vehicle real quickly to see if maybe Teresa was under there and, um, that was it," Remiker testified.

John Ferak of USA TODAY NETWORK-Wisconsin: 920-993-7115 or jferak@gannett.com; on Twitter @johnferak