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North Dakota man convicted in grisly deaths sentenced to life in prison

A jury found Chad Isaak guilty in the April 2019 stabbing and shooting deaths of four people at a property management firm in the city of Mandan.

A man convicted of stabbing and shooting four people at a North Dakota property management firm was sentenced Tuesday to life in prison without the possibility of parole.

A jury in August found Chad Isaak guilty in the grisly deaths of RJR Maintenance and Management co-owner Robert Fakler, 52; and employees Adam Fuehrer, 42; Bill Cobb, 50; and his wife, Lois Cobb, 45.

The four were shot and stabbed April 1, 2019, in the RJR building in Mandan, a city of about 20,000 people across the Missouri River from Bismarck. Investigators said the victims suffered more than 100 stab wounds.

Isaak was also found guilty of burglary, unlawful entry into a vehicle, and a misdemeanor count of unauthorized use of a vehicle.

Prosecutors recommended four consecutive life sentences without parole for each murder, along with nearly 16 years in prison for the other charges. An attorney for Isaak asked for life with the possibility of parole.

South Central District Judge David E. Reich accepted the state's recommendation, saying "the evidence is clear in this case that Mr. Isaak took the lives of four innocent people with a senseless act of extreme brutal violence."

Prior to the sentencing, family members of the victims read impact statements.

Fakler's daughter cried as she recalled her father. "My dad was a loving person who wanted to teach life lessons and help people grow as individuals," she said, telling Isaak that he is a danger to the public.

"I don't want another family to experience what we have," she continued. "The brutality and extremity of the actions you carried out are enough for you to be locked away. You have taken entire lifetimes away, and I hope you have nightmares."

The daughter of Bill Cobb, stepdaughter of Lois Cobb, said her life has never been the same since their murders.

The stepmother of Fuehrer told Isaak that he was a "monster" for what he did. "That hurts a lot," she said. "What you did to Adam was brutal, horrible."

Isaak also briefly addressed the court, saying: "I can honestly tell you I am not a murderer and that’s all I have to say."

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Isaak, a chiropractor and Navy veteran, lived at a Washburn property managed by RJR, but a motive for the slayings was never established. Washburn is located about 40 miles north of Mandan.

Chad Isaak, appears in court in Mandan, N.D., on April 5, 2019.James MacPherson / AP file

It was one of the most heinous crimes in North Dakota history, defense attorney Bruce Quick acknowledged in his opening statement. But he maintained during the nearly three-week trial that investigators didn’t seriously consider other possible suspects, including people who have either been evicted or sued by RJR, as well as a long list of disgruntled RJR employees who were fired.

The defense also maintained police failed to check out the ex-husband of a woman who allegedly had an affair with Fakler.

Prosecutors showed security camera footage from numerous businesses that authorities said tracked Isaak’s white pickup from Mandan to Washburn on the day of the slayings, along with footage from a week earlier that they said indicated the killer planned out the attack.

Forensic experts testified that fibers on the clothing of the slain workers matched fibers taken from Isaak’s clothing, and that DNA evidence found in Isaak’s pickup truck was linked to Fakler and possibly Lois Cobb.