BREAKING NEWS: Schaffhausen pleads guilty in murders of 3 daughters

HUDSON, Wis. - A former Wisconsin man spoke for the first time in a St. Croix County courtroom Thursday, entering a guilty plea in the murders of his three daughters.

Aaron Schaffhausen confirmed the pleas in a flat, emotionless voice as he responded to the judge's questions regarding his understanding of the legal proceedings.

"Are you pleading guilty because you are guilty?" asked the judge at one point. "Yes," Schaffhausen responded.

Along with the murder charges, Schaffhausen also entered a guilty plea to one count of arson. Authorities maintain he tried to burn down the house of his estranged wife Jessica after he slit the throats of his daughters, 11-year-old Amara, 8-year-old Sophie and 5-year-old Cecilia.

The girls were killed on July 10. In January Schaffhausen's defense attorney entered a plea of not guilty by reason of insanity. That plea was changed to guilty, but Schaffhausen and his defense team still maintain he was not of sound mind when he comitted the crimes. Whether he was insane at the time of the murders will be decided in the second phase of his legal proceedings.