MADISON, Wis. (AP) — A Wisconsin appeals court says a man who killed his young daughters to hurt his ex-wife was properly convicted.

Prosecutors charged Aaron Schaffhausen with killing his three girls at their River Falls home in 2012. He pleaded guilty but maintained he was insane. A jury determined, however, that he didn’t lack the capacity to understand his conduct was wrong.

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Schaffhausen argued the trial judge wrongly told jurors to decide who qualified as expert witnesses and failed to provide expert witnesses’ reports to the jury.

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The 3rd District Court of Appeals ruled Tuesday that letting jurors decide who was an expert was harmless and Schaffhausen didn’t identify anything in the reports that wasn’t presented to the jury in court.

Schaffhausen’s attorney says he’ll ask the state Supreme Court to hear the case.

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