HUDSON, Wis. (AP) -- Former co-workers of Aaron Schaffhausen testified Friday that they heard him say several times that he wanted to kill his ex-wife, their children and the man she was dating in the months before he killed his three young daughters.
Schaffhausen pleaded guilty last week to three counts of first-degree intentional homicide for killing his daughters -- 11-year-old Amara, 8-year-old Sophie and 5-year-old Cecilia -- in their River Falls home last July. But he maintained he was not responsible for the killings because of mental illness. Prosecutors maintain he killed the girls to take revenge on his ex-wife, Jessica Schaffhausen, because he was angry with her for divorcing him and for seeing another man.
Courthouse security will be tighter Monday when the trial resumes. The St. Croix County Sheriff's Office issued a statement late Friday saying deputies responded to a "potential threat" inside the county government building around 9:45 a.m. One individual was taken into custody and there's "no other known threat to the public," the statement said.
Reached by phone, Sgt. Jeff Kennett said authorities weren't providing further details on the incident. He said he couldn't comment on whether it was related to Schaffhausen's trial.
The statement said "no further comments are appropriate at this time" because the investigation is ongoing, but that access to the courthouse will require security screenings starting Monday.
The jury that began hearing Schaffhausen's case Tuesday will have to decide whether he was sane, which could result in a sentence of life without parole, or insane, which would mean he could be sent to a mental institution.
After the couple split up, Aaron Schaffhausen went to Minot, N.D., to work in construction and met the former co-workers who testified Friday.
One of them was Jeremy Michels, who wrote in an email to police after the killings that Schaffhausen had said things like: "I want to go kill my kids, then my ex-wife. After her, I will go to the man's house she is sleeping with, kill him, cut his head off, put it on a stake in my front yard and then I will sit back and have a beer."
Once, while they were playing cards, Michels testified, Schaffhausen talked of wanting to kill his family. When Michels told him that was weird or crazy, Schaffhausen responded, "Is it really?"
Schaffhausen also once told him, "I'll pay you to kill her," Michaels testified.
Jon Paul, who also worked and lived briefly with them in Minot, testified that Schaffhausen talked about killing his wife and kids about five or six times -- while drinking and not drinking. Paul said he told Schaffhausen he was sick of hearing the comments, and then Schaffhausen replied, "How much would it cost for you to do it for me?"
Michaels also testified that he once said something about Schaffhausen's ex-wife that caused him to leap off the couch and attack him with a broomstick.
"Don't you ever talk about Jess like that," Michaels recalled Schaffhausen threatening him.
Another former co-worker, Joe Rollag, testified that Schaffhausen was a hard worker and great friend but his work began to suffer in the months before the killings.
Rollag told jurors that Schaffhausen sometimes would cry in his van alone or sit there with a blank stare. While talking to his ex-wife, Schaffhausen sometimes was "calm and collected," Rollag said, but other times he was "angry and aggressive." And Schaffhausen also made threats toward his ex-wife's new boyfriend, he said.
Dr. Paul McMillan, a family practice physician from River Falls, testified earlier Friday that Schaffhausen came to him in April 2011, indicating he felt "depressed and hopeless most of the time." He said he determined that Schaffhausen had a moderately severe major depressive disorder. The doctor said Schaffhausen made a significant improvement on medication, but he prescribed a stronger dose the last time he saw him, in November 2011, because Schaffhausen reported feeling stressed about his divorce. He said Schaffhausen had not been suicidal or delusional.
McMillan also told Schaffhausen to get therapy, and Schaffhausen saw a counselor twice that year in River Falls.
The counselor, social worker Gretchen Link, testified Schaffhausen was concerned about his marriage and was feeling depressed. During the second visit, in August 2011, it seemed to her like his drinking had increased. It also seemed like at least part of the anger he was experiencing was directed at his ex-wife, Link said.