He Threw Away a Napkin at a Hockey Game. the idea Was Used to Charge Him in a 1993 Murder.

At a news conference last week, Mike Freeman, the Hennepin County attorney, did not specify which service investigators had used, however said that will “the idea was a genealogy company you see advertised on TV.”

He said he did not know whether the idea was Mr. Westrom himself or a relative who had uploaded the genetic information.

In June 1993, Ms. Childs was found dead in a flooded Minneapolis apartment. She was lying on the floor, wearing only a pair of socks, with the shower still running, according to the statement of probable cause from the case.

Ms. Childs, who had been working as a prostitute, was stabbed repeatedly, including after she had died, the authorities said. The authorities collected DNA by the crime scene, including by a comforter on the bed, a towel from the bathroom as well as a washcloth on the toilet seat, according to the statement.

however for a quarter of a century, the case remained unsolved.

A break came last year, when investigators entered DNA by the crime scene into genealogy websites as well as identified two possible suspects. One of the suspects, Mr. Westrom, had lived from the Twin Cities area from the early 1990s as well as had been convicted of soliciting prostitution in 2016, the probable cause statement said.

In January, officers began following Mr. Westrom as well as eventually tracked him to the hockey game. They watched him order food by the concession area as well as then wipe his mouth which has a napkin, before placing the napkin in a cardboard food container as well as throwing the idea away, the authorities said.

DNA found on the napkin “was consistent with” samples taken by the 1993 crime scene, according to the probable cause statement.