Son Sentenced in Stabbing of Father, Death of Mother

A year after he stabbed his mother to death and knifed his Emmy award-winning father because they wouldn’t give him their car keys, Michael Tonnessen pleaded guilty Monday to manslaughter and attempted murder charges and was sentenced to 12 years to life in prison.

“I did not want to make a determination as to how many years are appropriate. I wanted a life sentence,” said Deputy Dist. Atty. Kenneth Barshop.

“The family was concerned. They don’t want him out until he is no longer a danger to them or to himself.”

Tonnessen betrayed no emotion in court, but his lawyer, Deputy Public Defender Irv Rubin, said he was devastated.

“He’s very upset about the whole thing. He’s been in tears. He’s been to the point of not even wanting to discuss the case. It’s more than remorse,” Rubin said. “He feels that he certainly shortened his mother’s life tremendously and ruined his father’s life.”

Tonnessen, who both sides said has a history of emotional problems and alcohol abuse, had been drinking all day June 21, 1997. When he ran out of alcohol that night, he asked his parents for the keys to their car to go buy more. They refused.

Tonnessen, 25, then “made some comment about Satan, asking for power from Satan. Shortly after that is when the stabbing occurred,” Rubin said, citing a police report.

After the stabbing, his mother, Theresa Tonnessen, 51, ran outside the Stevenson Ranch home, but Tonnessen followed, according to Barshop. Neighbors saw the bloody couple emerge from the house, the father screaming for help.

Tonnessen then pumped his hands in the air, in victory, according to police.

When police arrived, he barricaded himself inside the house. He was eventually smoked out with tear gas four hours later.

His mother died that night.

His father, Kurt Tonnessen, has suffered emotional and financial troubles, Barshop said, but still won a second Emmy in the year that has passed since the crime. He is a cameraman with NBC’s Tonight Show, starring Jay Leno.

Tonnessen will be eligible for parole in 10 years but his lawyer said that would be unlikely. While he said his client does expect to walk out of prison at some point, it doesn’t matter when.

“He just doesn’t care about his life. I think he felt whatever he was given, he deserved,” Rubin said.