HUDSON, Wis. (WCCO/AP) — A father who admitted killing his three daughters in western Wisconsin won’t testify at his insanity trial, despite speculation going into Wednesday’s proceedings that he would.

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The defense has rested in St. Croix County Circuit Court where jurors will decide whether Aaron Schaffhausen is legally responsible for the girls’ deaths or whether his mental state means he’s not guilty because of his disease and should be institutionalized.

Outside the presence of the jury, the judge questioned Schaffhausen about his decision not to testify.

“It’s my understanding you are not going to testify today,” the judge said.

“I am not testifying today, no,” said Schaffhausen.

He hopes jurors believe he was insane when he killed his three daughters at their home in River Falls, Wis., last summer.

After the defense rested, the prosecution called witnesses to testify that Schaffhausen was angry about his divorce and that he made repeated threats to a man his ex-wife, Jessica Schaffhausen, was dating.

Josh Flanders, who dated Jessica Schaffhausen in the months before and after the divorce, testified that Aaron Schaffhausen threatened him on Facebook and over the telephone, demanding he stop seeing Jessica.

“He would say: ‘No, I am not threatening you, but you should watch your back. Bad things are going to happen to you,’” Flanders said.

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Flanders’ mother, Judy Flanders, said she also received phone threats from Schaffhausen, which she eventually reported to police.

“If you don’t want to see your son’s life shortened, he needs to stop f—ing my wife,” Judy Flanders reported Schaffhausen as saying.

Lisbeth Danielson, whose child had class with one of Schaffhausen’s daughters, said Schaffhausen was angry and depressed about the impending divorce, and that he often demanded information on who Jessica Schaffhausen was dating.

She also said that Schaffhausen, due to the divorce, wouldn’t talk to his girls for weeks at a time, making them upset. Danielson testified that she texted Schaffhausen, saying that he should talk to them.

“He wrote [back] that they would be fine without him, that Jess would move to Springfield and find a new husband, and they will have a new dad,” Danielson said.

On Tuesday, the jury heard from a medical expert hired by the defense. Forensic psychologist Dr. John Reid Meloy described Schaffhausen as a “complicated individual” who was insane at the time of their murders.

Meloy used four different computer-based tests to conclude Schaffhausen suffered from major depression. He said Schaffhausen was in an “abysmal tunnel” when he murdered his girls.

“He would cry easily, was volatile, was angry. He was threatened, he was obsessed with Jessica. He had many death images, which is a part of the diagnosis of major depression,” Meloy said.

Tuesday’s testimony differed from that of the court-appointed psychiatrist who testified on Monday. Dr. Ralph Baker testified that he found Schaffhausen was legally sane when he killed the girls, ages 5, 8 and 11, on July 10, 2012.

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