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He’d planned to take his new baby daughter out trick-or-treating that October night in 1993.
Brian Dietrich — the son of [then] Clayton County Sheriff Verdean Dietrich — was known for his biker lifestyle and “living off the land” in rural Garnavillo, Iowa, but made regular trips across the Mississippi River to Prairie du Chien, Wis., to sell ginseng.
He’d made such a trip Saturday, October 30, 1993, his mother, Bonnie Dietrich, said.
According to Lt. Lauren Knutson of the Crawford County (Wisconsin) Sheriff’s Office, Dietrich — along with his girlfriend and her brothers — was hanging out at the downtown Schooner Bar in Prairie du Chien.
“At some point in time, there was a scuffle [and] Brian was struck once by one of the brothers,” Knutson told WMTV (NBC) Channel 15 for a story that aired May 17, 2009.
The 30-year-old Dietrich headed home, walking toward the bridge connecting Prairie du Chien with Clayton County, Iowa, but never made it home.
Dietrich’s girlfriend reported him missing several days later, insisting he was in the river.
Knutson firmly believed people knew more than what they were saying, and said on a scale of zero to ten, he’d put [his suspicions] at a ten.
“What we know is what the people with him have told us that night,” he said. “All indications are Brian didn’t jump into the river voluntarily. There was just nothing that ever said he was suicidal.”
Dietrich’s body wouldn’t turn up until the following May — entangled in the roots of Indian Isle.
Indian Isle — a one-mile wooded island on the Mississippi River — could be accessed only by boat within the Crawford County jurisdiction. Home to about 20 seasonal cabin dwellers, the secluded island lay one mile south of the Mississippi River bridge near McGregor, Iowa.
On Saturday, May 28, 1994 — Memorial Day weekend — a suspicious odor led one resident out to the shore to investigate.
He discovered the body on the shore; fully clothed, the man lay face down in the sand. The resident immediately notified the Crawford County (Wis.) Sheriff’s Department.
Joined by officials from the Clayton County Sheriff’s Office and the Wisconsin Department of Natural Resources, the deputies examined the body for a cause of death. They could find no wounds, but did find the victim’s clothing and wallet nearby.
The remains were those of Brian Dietrich.
Lt. Knutson, on call at the time, was one of the first responders.
“[The body] appeared to have been in the river for several months,” Knutson told the Dubuque Telegraph Herald in an interview for a story published May 30, 1994.
Dietrich’s body was transported to the University of Wisconsin for an autopsy, and though the coroner eventually ruled the death a drowning, investigators couldn’t shake the feeling they’d had from the very beginning; they strongly believed there was more to this death.
Lauren Knutson retired from the Crawford County Sheriff’s Department in 2006, but never truly left the work behind him.
“This was just too good a case to let go. There were just too many question marks… too many red flags,” he said.
Crawford County Sheriff Jerry Moran and other investigators felt the same way; the final moments of Dietrich’s life had led them to suspect foul play.
In May 2009, the Crawford County Sheriff’s Department re-opened the investigation. Few tips trickled in, with none producing any significant breakthrough.
Another year passed, and in June 2010 — with retirement looming in six months — Moran decided to make the case one of his top priorities.
“I want to develop a plan,” he told the Telegraph Herald in a story published June 5, 2010. “There isn’t much happening, [but] there are some potential witnesses to be interviewed yet.”
The following week Moran met with Captain Dale McCullick and the retired Knutson, both of whom had conducted the bulk of the work on the case.
Dietrich’s mother told the Telegraph Herald she’d never been satisfied with the coroner’s ruling and believed she knew the truth about what really happened to her son. She insisted she would never give up hope.
“I’m not gonna settle for someone getting away with it,” she said.
Brian Dietrich was born April 5, 1964.
Although some documents cite his date of death as Oct. 30, 1993 — the day he went missing — his gravestone bears the date May 28, 1994 … the day his body was recovered from Indian Isle.
Services were held at 11 a.m. on Wednesday, June 1, 1994, at St. Paul Lutheran Church in Garnavillo. Dietrich was buried in the Guttenberg Cemetery in Clayton County, Iowa.
Survivors included his parents, Verdean and Bonnie (LaDage) Dietrich of Garnavillo; a daughter, Haley; two sisters, Shelley of Garnavillo and Jan Heck of Dallas, Ga.; maternal grandmother, Mildred LaDage of Guttenberg; and friend, Bonnie Bailey of Guttenberg.
The family asked that memorials be made to the Garnavillo Boy Scout Troop 43 and the Osborne Conservation Center.
Brian’s father, Verdean Lyndall Dietrich, had spent most of his career in law enforcement but passed away on May 28, 2014, without ever knowing for certain what happened to his son. After retiring as Clayton County Sheriff in 2001, Verdean Dietrich went on to serve as Chief of Police for Garnavillo from 2001 through 2010. He was survived by his wife and two daughters.
If you have any information about Brian Dietrich’s unsolved death, please contact the Crawford County (Wis.) Sheriff’s Office at 608-326-0241, Crime Stoppers at 866-779-7297 or 608-326-8933, or the Clayton County (Iowa) Sheriff’s Office at 563-245-1234.