Jeff Thiel's daughter believed he committed double murder. Police found other evidence

Thirty years after a brutal double murder in Wisconsin, the daughter of one of the original suspects comes forward — reigniting the case all the way to trial.

For as long as she can remember, Heather Thiel believed her father was a killer.

She was so convinced that she twice urged authorities to examine whether he was responsible for a horrific, unsolved double murder that shook rural Wisconsin more than three decades ago.

But her role in the investigation into the slaying of Tim Mumbrue and Tanna Togstad led to an outcome she never could have imagined: three years ago, authorities concluded that her cousin, not her now-deceased father, fatally stabbed the couple on March 21, 1992.

DATELINE FRIDAY SNEAK PEEK: Raising the Dead01:59Just as head-spinning, that cousin, Tony Haase, was acquitted in the murders earlier this year. During a nearly monthlong trial, Haase’s lawyers made the case that the evidence pointed at Heather Thiel’s dead father, Jeff Thiel.

For Heather Thiel, who is 40 and works at a group home for mentally ill adults, the whiplash of the last three years left her questioning longstanding beliefs and wrestling with a familiar feeling.