The man accused of killing his three daughters in their River Falls home last summer is now pleading not guilty by reason of insanity.

A public defender representing Aaron Schaffhausen entered the plea Wednesday. A hearing is set for Thursday morning.

The move is a change of strategy for Schaffhausen's defense. Last month, assistant public defender John Kucinski missed a deadline for notifying the court of an insanity plea.

It appeared then that the defense would rely on arguments that law enforcement failed to follow proper procedures in questioning and arresting Schaffhausen.

Schaffhausen faces three counts of first-degree murder and one of attempted arson in the killings of his three daughters, who were 11, 8 and 5 years old.