A Minnesota man has been charged with murder after investigators matched DNA from a napkin he threw out at his daughter's hockey game to evidence they had on file. 

52-year-old Jerry Westrom was linked to the 1993 stabbing death of Jeanne Ann Childs after cold case investigators compared samples from the scene to a public genealogy database. The case had been reopened in 2015, in light of advances in DNA screening technology.

Investigators sent samples from the scene to the Minnesota Bureau of Criminal Apprehension and a DNA testing company. The samples turned up Westrom's name after being compared to data on the public DNA database GEDmatch

That match meant that either Westrom or a close relative had used the website. They used that information as the basis to look into Westrom's online presence. From there, they followed Westrom based on where he said he was going to be and recovered a napkin he used at a game in Wisconsin in January.

Authorities said they thought of using the database after a similar method was used to capture the Golden State Killer, a case that had obsessed detectives and amateur true crime sleuths for decades. 

“We all learned quite a bit from the Golden State Killer,“ said Hennepin County Attorney Mike Freeman told Minneapolis' WCCO.

Freeman explained that the way they went about obtaining the sample was entirely legal. 

“When you discard things in the trash, the Supreme Court often says it’s free game," Freeman said. "And so he discarded the napkin in a container and threw it in the trash, so they could get it."

Westrom has denied the allegations and is currently free after paying a $500,000 bail.