MINNEAPOLIS (WCCO) — When 18-year-old Carrie Richter and 20-year-old Dustin Baity didn’t show up for a gathering on Christmas Day 1998, their families grew suspicious.

The couple was later found strangled and stabbed in the northeast Minneapolis apartment they shared.

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“Homicides are never over and DNA is the great tool of investigators and prosecutors,” said Hennepin County Attorney Mike Freeman.

After years without solid leads, police reopened the cold case in 2007. That’s when Sgt. Chris Karakostas began working it.

“Technology changes, so things you didn’t think could be tested before now can be tested,” Karakostas said. “You reassess, you go back, you take a look at everything that was in there. Maybe you missed something.”

Jason Preston (credit: Hennepin County)

Jason Preston (credit: Hennepin County)

That something turned out to be a single drop of blood that didn’t belong to the victims. And on March 6, 2013, a national DNA database pointed to a California convict, 35-year-old Jason Richard Preston. It was a perfect match.

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Since the discovery, more evidence found at the couple’s apartment links Preston to the crime. Investigators, however, would not elaborate on the nature of that evidence.

For Dustin Baity’s sister, Dawn, it brings a bittersweet closure to their very difficult and grief-filled journey.

“I always had hope that something would happen, you know,” Baity said. “But you kind of put it away.”

Jason Preston is serving time in a California prison for a violent home invasion. He is not scheduled to be released for another 24 years.

County Attorney Freeman says there is no rush to extradite or bring Preston to trial now that he is charged with four counts of first- and second-degree murder.

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Anyone with information about his whereabouts on Dec. 24, 1998 or how he met the couple is asked to contact Minneapolis Police Sgt. Chris Karakostas at 612-490-2991.