Investigators have reanalyzed evidence to solve the 1991 murder of a 38-year-old woman in American Canyon.
Business owner Kin Ko was working at Sam's Market with her 14-year-old daughter on March 23, 1991, when two suspects entered the convenience store, investigators said.
The first suspect stayed at the door, possibly as a lookout, while the second demanded money from the cash register. The second suspect took the money from the register and backed away from the counter, according to the Napa County Sheriff's Office.
Ko produced a handgun from behind the counter and ordered the suspect to stop. Ko then approached the suspect and attempted to take the cash back, according to the sheriff's office.
A struggle ensued between Ko and the suspect, and they fell to floor, and Ko was stabbed once in the back before the suspects fled, investigators said.
Ko's daughter called 911, and deputies searched the area for the suspects. Ko was transported to a hospital, where she succumbed to her injury.
At the time of the initial investigation, detectives attempted to locate a potential suspect, identified as Michael Lantz of American Canyon and Vallejo, but were unable to find him.
Traditional forensic processing methods available in 1991 did not reveal any useful forensic evidence on the murder weapon, but investigators were able to trace the weapon sale back to a relative of Lantz, according to the sheriff's office.
While evidence produced from the original investigation indicated that Lantz was the primary suspect in numerous armed robberies, there was no DNA evidence on which to arrest him, investigators said.
With little evidence to support a criminal filing, the case went cold.
In 2009, detectives at the Napa Police Department and Napa County Sheriff's Office reviewed the case using modern DNA analysis.
In 2012, DNA evidence on the murder weapon linked Lantz to the homicide.
Detectives learned that Lantz had died in federal prison in 1994 and that Ko's husband had also passed away.
Ko's surviving relatives were notified of the circumstances surrounding their mother's death, allowing some final closure for the Ko family, according to the sheriff's office.