It was December of 2014, and Michael Usry had no idea why a pair of Louisiana State police officers showed up at his New Orleans home, asking him to accompany them to the precinct for questioning.

He was even more confused when an FBI agent asked to swab his cheek for DNA.

“They wouldn’t tell me anything,” Usry, now 43, tells The Post. “I was like, ‘Am I being accused of a crime? Do I need a lawyer?’ ”

It was only later that Usry, a low-budget filmmaker, learned he was a suspect in the 1996 murder of 18-year-old Angie Dodge. There were a few things that pointed to him: He’d visited Idaho Falls, Idaho, where the victim was killed, during the same time frame of the murder. He had directed a 2010 film called “Murderabilia,” which — according to the search warrant — “dealt with some sort of homicide or killings.”

But the main reason cops showed up on Usry’s doorstep was his DNA. When genetic evidence from the crime scene didn’t match anything in the national law-enforcement database, the police ran a familial DNA search on Ancestry.com, the world’s largest for-profit genealogy company.

They found a close match between semen found at the murder scene and the DNA of Usry’s dad, who had donated his saliva to Ancestry as part of a genealogy project with his church. When the elder Usry was deemed too old to be a suspect, it led detectives to his son. Although the younger Usry had never used Ancestry or any other genealogy service, his dad’s DNA was enough for a judge to issue a warrant.

Even after Usry’s DNA was tested and his name cleared — which took weeks — he didn’t rest easy.

You can read more in an article by Eric Spitznagel and published in the New York Post web site at: https://nypost.com/2022/10/01/how-police-can-use-your-dna-to-solve-crimes-without-consent/