Man convicted for son-in-law’s murder in Spokane Valley dies in prison at 89

An 89-year-old man who assisted in the murder of his son-in-law in Spokane Valley has died after two decades in prison.

Morris “Mel” Goldberg and his ex-wife, JoAnn Peterson, were convicted of first-degree murder for the Nov. 18, 1991, killing of Peter Zeihen. Peterson shot Zeihen in the head with a 12-gauge shotgun outside his Spokane Valley apartment. Goldberg helped plot the attack and drove the getaway car.

Janelle Guthrie, a spokeswoman for the state Department of Corrections, said Goldberg died on April 22 at Kadlec Regional Medical Center in Richland, a day after he was taken to the hospital from the Coyote Ridge Corrections Center in Connell.

“He was tested for COVID-19, but results were negative,” Guthrie said in an email. “The department will conduct a review of this death.”

Zeihen was 40 years old and in the midst of a bitter child-custody dispute with his estranged wife when he was murdered. He bought a handgun and a bulletproof vest after Peterson shot at him with a .357 handgun in an earlier attempt on his life.

Detectives suspected from the beginning that a family member might have killed Zeihen, but the case languished for nearly nine years before two of Goldberg and Peterson’s adult children traveled from Denver to Spokane and spilled details of the murder to sheriff’s deputies.

At the time, federal agents also were investigating Peterson for possessing a machine gun at her remote home near Moyie Springs, Idaho. She and Goldberg had protested the actions of federal law enforcement agencies at Ruby Ridge during the Randy Weaver standoff in 1992.

In court, Goldberg and Peterson asserted they stalked and killed Zeihen because he had sexually abused their granddaughter, then a toddler. Police and child welfare investigators found no evidence to substantiate that claim.

At his sentencing in 2000, Goldberg, then 70, expressed no remorse, rambled about government misdeeds and suggested God’s words in the Old Testament justified his involvement in Zeihen’s murder.

Goldberg later appealed to the state Supreme Court and had his prison term reduced from life without parole to nearly 27 years. In 2009, he sought clemency from then-Gov. Chris Gregoire, claiming he was “self-reformed and rehabilitated” and in poor health. His request was denied.

Peterson remains incarcerated at the Washington Corrections Center for Women in Gig Harbor.