HUDSON, Wis. – On the kitchen wall where the Schaffhausen sisters' heights were marked at their River Falls home, an officer investigating their murders noted three marks in red ink for 11-year-old Amara, 8-year-old Sophie and 5-year-old Cecilia dated July 10, 2012 — the last day of the girls' lives.

It was one of the many details presented in a St. Croix County courtroom Friday as prosecutors methodically continued trying to convince jurors that Aaron Schaffhausen was sane, knew right from wrong and was in control of his actions when he killed his daughters that day.

After a weekend break, the case could wrap up and go to the jury as early as Tuesday.

Schaffhausen pleaded guilty at the end of March to his daughters' deaths, placing the legal burden on his lawyers to prove that he was insane at the time and should be sent to a mental institution instead of prison. They presented their case first, wrapping up midweek after testimony from a forensic psychologist who said Schaffhausen had "major depression" accompanied by personality traits that caused him to lack substantial capacity to conform his conduct to the law, Wisconsin's legal definition.

Friday, prosecutors called more witnesses, including state crime lab workers, police investigators and an assistant medical examiner. The workers described how they went to the house and marked, photographed and later DNA-tested bloodstains on carpets, door frames and a clothes washer, among other places.

Family members in the gallery got emotional when some graphic photos of bloodstains were shown to the jury on large television screens. Schaffhausen continued to sit still, as he has throughout the two-week trial, appearing not to react.

Defense attorney John Kucinski objected to the hours of testimony on DNA and other evidence, saying it was unnecessary because his client had already pleaded guilty to the crimes and the testimony wasn't relevant to Schaffhausen's mental state.

Prosecutor Gary Freyberg argued it would show that Schaffhausen was in control of his actions; Washing clothes with blood on them, for instance, shows Schaffhausen knew right from wrong and was trying to conceal or destroy evidence, Freyberg argued.

Prosecutors contend Schaffhausen killed the girls to hurt his ex-wife after the couple divorced about six months earlier. They are expected to call their hired mental health expert to testify Monday.

Pam Louwagie • 612-673-7102