Lawyer: Schaffhausen erratic before killing girls

House where 3 sisters were killed to be auctioned
Aaron Schaffhausen

The attorney for a man accused of killing his three young daughters in River Falls said his client was spiraling out of control in the months leading up to the slayings last July.

Aaron Schaffhausen, 35, has admitted killing his daughters — ages 11, 8 and 5 — at their home in River Falls, Wis. But Schaffhausen is seeking to convince a jury that he’s not responsible due to mental illness.

In opening statements Tuesday at his trial in Hudson, defense attorney John Kucinski said Schaffhausen became increasingly erratic and obsessive after he and his ex-wife, Jessica, divorced in January. He said Schaffhausen called Jessica constantly and sometimes threatened to hurt her or the girls.

Prosecutors said Schaffhausen planned the killings and that contradicts his claim of mental illness.