When Bill Marquardt was acquitted of murdering his mother Mary, Jon Theisen says it wasn't because of a lack of effort.
Both he and assistant Roy Gay had set day-to-day responsibilities aside to work on it for a month.
"Law cases, criminal investigations are not like fine wine or cheese. They don't get any better as they get older," Theisen said.
Marquardt's attorney presented testimony through a prisoner's letters.
"We couldn't cross examine that person because he's dead."
And when a witness talked to police two days after the trial had started, prosecutors say they didn't have time to play catch-up.
"It's pretty hard to follow up and find out credibility, corroborate the story of this witness."
Then there's Marquardt's family, who Theisen says was over their anger by the time Marquardt was on trial, and they were in his corner.
"That damages our case. Six years later there were a variety of these factors that made it an extraordinarily difficult case to present."
The jury didn't buy their case either, much like the jurors in Chippewa three weeks prior, who decided in favor of former firefighter Thomas J. Brick.
"These happen to publicly proclaim that we have some improvements to accomplish."
Theisen says they'll keep prosecuting with a team of at least two lawyers per case from here forward, and improve their teamwork with the Sheriff's Department.
He still considers the office to be a successful one, and says they'll be perceived as tough lawyers to beat in court soon enough.
"We're not there yet, obviously. We will be there."