FT. COLLINS, Colo. -- Tim Masters walked away from the Larimer County Justice Center a free man Tuesday morning. After spending nearly a decade incarcerated at the Buena Vista Correctional facility, skin cell DNA tests vindicated the man who has sworn all along he was innocent of the murder of 37-year-old Peggy Hettrick.

Hettrick was stabbed in the back, sexually assaulted then mutilated on Feb. 11, 1987. Her body was found in a field near Masters' home. He was convicted without any DNA evidence linking him to the crime.

Richard and Selma Eikelenboom run a lab in the Netherlands that specializes in skin cell DNA detection.

"Skin cell investigations are still in their (infancy)…it’s not performed worldwide very often. People do it on an occasional basis," said Richard Eikelenboom, of Independent Forensic Services.

As it was explained, he said skin cell DNA tests look for DNA profiles that saliva, semen and blood may not yield.

He said skin cell DNA is often left behind in violent crimes like Hettrick’s where the victim is grabbed and dragged. He said the perpetrator’s sweat cells can be found embedded in the victim’s clothing.

"When the perpetrator is dragging the body in the field … (when they are strangled) he’s leaving DNA," said Eikelenboom.

So far Richard Eikelenboom said his lab tests have exonerated at least six people in Europe and Australia but seeing the result of their work in Masters' case was overwhelming.

"It's always very special when you get someone out, especially in this case a life sentence," said Eikelenboom.

With Masters vindicated, the question remains: Who killed Peggy Hettrick?

DNA tested in the Eikelenboom’s lab points the finger back at a former suspect said Masters' Attorney David Wymore: Hettrick’s old boyfriend.

It’s unclear if that evidence will be used to reopen the homicide investigation.