NEW YORK — A Minnesota judge sentenced a man to life in prison without parole Thursday for the death of his first wife, 13 years after police said he shot her over their financial troubles and lied to investigators that it happened during a home invasion.

Several of Heidi Firkus' friends and family gave emotional victim statements before the judge sentenced her husband Nick Firkus, 40, for his crimes. For years, Nick Firkus maintained he was innocent and that a mysterious home intruder was involved in her death. However, investigators found there was nothing to back up his alibi and found evidence that he lied to his wife about their debts.

"Every homicide is a tragedy. This one is particularly egregious. He hid behind his status for too many years," Elizabeth Lamin, the assistant district attorney for Ramsey County, Minnesota, said.

On April 25, 2010, Heidi Firkus called 911 saying there was a break-in and stopped talking after a gunshot went off, according to the audio from the call. Police found her dead and her husband wounded in the leg from a gunshot.

"20/20" will take a deep look into Heidi Firkus's murder and the 13-year-long investigation in an episode airing this Friday at 9 p.m. ET and streaming the next day on Hulu.

Nick Firkus told investigators that he fought over a shotgun with the intruder and that it went off, hitting both him and his wife.

Firkus also told officers that the couple was facing serious financial problems and were set to be evicted, but that he kept those issues secret from her, his family and their friends.

No suspects were named and no one was arrested for years.

However, investigators were still looking into Nick Firkus' role in his wife's death, especially since there were discrepancies in his story. There were no signs of a break-in in the house and only Nick Firkus' DNA was found on the shotgun.

He was arrested in May 2021 and charged with first and second degree murder. Prosecutors said that Nick Firkus killed his wife to hide from the shame of their financial troubles.

A jury convicted Nick Firkus on both charges on Feb. 10 after deliberating for 10 hours.

Peter Erickson, Heidi Firkus' brother, blasted Nick Firkus during his impact statement.

"The realization that everything Nick was telling us. To have audacity obviously inconsistent to Heidi's character [it's] insulting," he said.

Linda Erickson, the victim's mother, got emotional during her statement thinking about the years of life lost.

"Because of the unthinkable actions of one person, she was robbed and those who loved her were robbed of participating in that adventure with her," Linda Erickson said.

Nick Firkus' attorneys contended their client's story was the truth and that his wife's death was caused by the break-in.

Nick Firkus again reiterated his claims that he didn't murder his wife before the judge sentenced him.

"I will maintain my innocence until my dying last breath," he said.

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