PLACERVILLE (CBS13) – A witness in the murder trial of Steven Colver, charged with killing his girlfriend’s mother, says Colver told him he killed the woman.

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Colver is charged with first degree murder in the death of 47-year-old Joanne Witt in June of 2009.  Witt’s daughter Tylar, who was 14 at the time, has already pleaded guilty in the case and is testifying against Colver for a reduced sentence.

Today, a friend of Colver’s, Matthew Widman, who is also known as “God”, testified in the case.  Widman said that he and Colver smoked weed and did some coke.  He also says, Colver, whom he calls “Boston”, showed him a bag with a knife in it.

“Boston proceeded to tell me he killed Ty’s mom.  He said ‘I stabbed her in the stomach and throat and put blanket over her’,” Widman said on the stand.

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On cross examination, Widman confirmed Colver said he stabbed Joanne in the stomach.  An important detail because she was not stabbed in the stomach.

He also said he never heard Colver threaten Joanne Witt.  But he did hear Tylar wish her mother was dead several times. 

The prosecution says Colver is troubled man who killed Joanne Witt because she would have sent him to prison for statutory rape.  Colver was 19 at the time of the crime.

The defense is trying to prove that Colver confessed to killing Joanne to protect Tylar who they claim actually killed her mother.

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Joanne Witt’s body was found in her home on Tattinger Court in El Dorado Hills on June 12, 2009.  Colver and Tylar Witt were arrested a few days later hiding behind a restaurant in San Bruno.