MINNEAPOLIS (WCCO) — Nearly 30 years since Jacob Wetterling’s abduction, authorities have released most of the files related to the investigation.

Wetterling was kidnapped and murdered in 1989. Two years ago, Danny Heinrich confessed to the crimes and led authorities to the location of Wetterling’s remains.

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More than 40,000 pages of documents were released Thursday, and 4,000 of those pages were left out because a judge ordered them to be returned to the FBI. The Stearns County Sheriff’s Office held a press conference to detail the release of the files.

Stearns County Sheriff Donald Gudmundson said one of the “fatal flaws” of the investigation was the FBI interrogation of Danny Heinrich and that Heinrich was not the major suspect from the beginning of the investigation.

Description of Suspect:

Victims from the Paynesville assaults, the boy from Cold Spring, and Aaron Larson and Trevor Wetterling all give similar descriptions of the suspect, which point to descriptions of Heinrich. Authorities also received information that Heinrich should be considered a suspect for the Paynesville assaults, the Cold Spring assault and abduction, and Jacob Wetterling’s abduction and murder. In January 1990, a vehicle belonging to Heinrich had been repossessed and authorities contacted the current owner of the vehicle. The owner voluntarily drove the vehicle to detectives, who had the Cold spring boy sit in the vehicle. He described it as very similar to the car in which he was abducted, rating it as an 8 or 9 out of 10 in similarity.

(credit: Stearns County Sheriff’s Office)

A victim from the Paynesville incidents came to the sheriff’s office less than 48 hours after Wetterling’s abduction to say he believes the Paynesville assaults and Wetterling’s disappearance are related. Investigators did not follow up that lead for two months.

(credit: Stearns County Sheriff’s Office)

(credit: Stearns County Sheriff’s Office)

Police Lineup:

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In a 1990 lineup to which Heinrich consented, the boy from Cold Spring does not pick him out. There was no voice lineup, and not all of the boys involved in the Paynesville assaults were present for the lineup, nor were Aaron Larson and Trevor Wetterling.

(credit: Stearns County Sheriff’s Office)

Heinrich Arrest and Release:

In 1990, Heinrich was arrested, interrogated, and released. There is no mention of Heinrich following his release until background investigations are noted in March and April of 1990. After an interview with Duane Hart in 1991, who was a convicted sex offender in custody at a Minnesota correctional facility and was a suspect in several of the abduction cases, there was no mention of Heinrich in the files for more than 20 years. Hart’s interview provided crucial information about Heinrich. In the interview, Hart tells investigators that Heinrich asked him how to get rid of a body. According to Gudmundson, it appears no follow-up investigation was pursued based on the information provided by Hart.

(credit: Stearns County Sheriff’s Office)

Heinrich Confesses to Crimes:

In October 2015, Heinrich is arrested on child pornography charges, In August 2016, Heinrich provides a statement regarding Wetterling’s abduction and murder. He then leads police to the location of Wetterling’s body.

(credit: Stearns County Sheriff’s Office)

Concluding the conference, Gudmundson admitted that the Wetterling investigation was badly botched — an allegation many have long suspected. However, never before has the department admitted the details of the mistakes.

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“We can’t change what happened, but we can learn from it,” Gudmundson said.