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Two Years After Four People Were Found Stabbed Around 100 Times, Navy Vet Convicted of Gruesome Quadruple Murder


Jurors convicted a Navy veteran on Friday of killing four people who were stabbed some 100 times, combined—in a gruesome quadruple murder that even his defense attorney reportedly described as one of the most heinous crimes in North Dakota history.

Prosecutors used surveillance footage and DNA evidence to win the conviction of 47-year-old Chad Isaak, who denied being the man who killed four people inside a property management company: RJR Maintenance & Management co-owner Robert Fakler, 52, Adam Fuehrer, 42, and married couple William Cobb, 50, and Lois Cobb, 45, according to The Associated Press. Three of the victims were also shot.

A jury rejected Isaak’s defense, returning guilty verdicts on four counts of murder and a count each of burglary, concealment within a vehicle, and unauthorized use of a vehicle.

The horrendous nature of the crimes was undisputed. Prosecutors and the defense in the city of Mandan, North Dakota wrangled over the sufficiency of the evidence. Isaak’s lawyer argued that investigators wore proverbial blinders in viewing Isaak, a chiropractor and Navy vet, as the killer, and failed to investigate other people with motive, such as the husband of a woman with whom Fakler was having an affair.

The state maintained that Isaak was the person seen leaving property management company RJR on April 1, 2019 and taking a company vehicle. Surveillance footage showed Isaak’s white pickup truck heading from Mandan to his city of Washburn that day.

Kyle Splichal, who worked at the North Dakota State Crime Lab in 2019, testified that DNA evidence from Fakler and possibly Lois Cobb was in that vehicle, according to The Bismarck Tribune. There was a 1 in 482 chance that it could have been anyone but Fakler, he said.

Fibers investigators found on Isaak’s clothing looked the same as those on Fakler’s, Fuehrer’s, and the Cobbs’ clothes, said ATF forensic chemist Amy Michaud.

“They were indistinguishable,” she said.

Defense attorney Luke Heck tried to challenge her on the evidence chain of custody during cross-examination and pointed out that the Mandan Police Department handled labeling the evidence and gave her advice on what to test.

Sentencing is pending.

[Screenshott via KXMB]

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