Napkin helps police crack 32-year-old murder case

Suspect, 66, is scheduled to appear in court

The mystery of the sexual assault and murder of a US teenager in Washington state has been resolved 32 years after the crime thanks to a discarded napkin, DNA tests and genetic genealogy.

Gary Hartman, 66, has been arrested and is scheduled to appear in court today.

It began on March 26, 1986, when 12-year-old Michella Welch disappeared while playing with her two young sisters at a park.

A police dog found her remains that evening in a ravine, but the investigation bogged down and was eventually filed as unresolved. Fast forward to the 21st century, when progress came thanks to genetic genealogy, with its vast databases.

The technology led police to two brothers. They were placed under surveillance as police waited for a chance to verify their genetic profiles.

Gary Hartman recently ate at a restaurant, oblivious to undercover investigator sitting at a neighbouring table. When Hartman left, the investigator collected his used napkin and sent it to a lab for analysis — and discovered that the DNA matched that found on Michella’s body.