A SON IS DETERMINED TO PROVE HIS FATHER KILLED HIS MOTHER - IS HE RIGHT, OR DID HIS MOTHER COMMIT SUICIDE?

"48 Hours: Father and Son: The Verdict"

May 9, 2015 - 10:00 PM, ET/PT

From the start, Johnny Wall maintained the death of his ex-wife, Uta von Schwedler, was a suicide. To her son, Pelle Wall, it always was murder, and he was determined to have his father face a jury of his peers.

Susan Spencer and 48 HOURS investigate the death of von Schwedler in 2011, her son's efforts to prove Wall killed her, and the court case against Johnny Wall in "Father and Son: The Verdict" to be broadcast Saturday, May 9 (10:00 PM, ET/PT) on the CBS Television Network.

"Just because you don't get along with somebody doesn't insinuate that you want to hurt them," Wall told investigators in a deposition to be broadcast on 48 HOURS. "And I never, ever, ever wanted to hurt Uta."

48 HOURS has been covering the von Schwedler case for four years. Von Schwedler, a university research scientist, was found submerged in the bathtub of her Salt Lake City, Utah, home by her then-boyfriend, Nils Abramson. It took six weeks for the autopsy report to be released, which listed the cause of death as drowning. The manner of her death was listed as "undetermined," leaving open the possibility of suicide. Evidence at the scene even suggested von Schwedler might have killed herself.

But Pelle Wall believed his father killed his mother. The couple had long-standing issues that began after their 2006 divorce. To get people to believe him, however, Wall, who was 17 at the time of his mother's death, risked everything, including his own safety and that of his siblings, his relationship with his father and future financial security. Could he prove it?

Johnny Wall, a pediatrician, has maintained he had nothing to do with his wife's death. Police interviewed Wall the night his ex-wife was found dead. He was arrested and charged in 2013 with killing his wife. He went on trial in February 2015.

"My father being put on trial is the culmination of a lot of work. I will be sitting across from him. I'm sure he doesn't have warm feelings for me," Pelle Wall tells 48 HOURS. "His conviction is incredibly important to me."

Would the son get justice? Or did von Schwedler actually commit suicide?

Spencer and the 48 HOURS team tell the story through interviews with Pelle Wall, investigators, family members and von Schwedler's co-workers. 48 HOURS: "Father and Son: The Verdict" is produced by Marcelena Spencer, Aimee deSimone, Josh Gelman, Avi Cohen and Bill Kerig. Charlotte Fuller is the field producer. Peter Schweitzer is the senior producer. Susan Zirinsky is the senior executive producer.

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