"Kimball's DNA evidence has not been found anywhere near the crime scene or on Hettrick's body," a source told 9Wants to Know.
The Denver Post recently reported the Colorado Attorney Generals' office and the FBI were investigating Kimball as a possible suspect in Hettrick's murder.
9NEWS Legal Analyst Scott Robinson says without a DNA match to Kimball, he is no longer a viable lead for investigators.
"Without forensic evidence connecting Kimball to either the crime scene or the location where the body was found, in light of his denials, they have nothing to work with," Robinson said. "It's theoretically possible to commit a crime and not leave a DNA trail, but it's darn hard."
Earlier this year, investigators tested the DNA evidence found on Hettrick using a new technique called "touch DNA." The newly discovered DNA evidence does not belong to Kimball, according to the source.
Masters was freed in 2008 after DNA testing cast doubt on his guilt. Master's DNA was not found on Hettrick's body or at the crime scene. At the time of Masters' conviction in 1999, "touch" DNA testing was not available.
In 2008, the Colorado Attorney General's office took over the Hettrick investigation. A grand jury has been convened in the case.
Recently, The Denver Post discovered similarities between Hettrick's unsolved murder and the unsolved murder of Catrina Powell. Kimball, a convicted serial killer, is the main suspect in Powell's murder.
In 2009, Kimball admitted to killing four people and is prison after pleading guilty to second-degree murder in the disappearances of three Colorado women in 2003 and his uncle Terry Kimball in 2004.
Powell's naked body was found behind a Westminster strip mall in 2004. Her hands had been cut off and police believe the killer poured acid on her body.
The Post quotes an autopsy report that showed Powell's killer had sliced one of her breast's nipples and tissue from her groin. Hettrick was also sexually mutilated.
But there are also differences between the Hettrick and Powell murders.
Powell had been beaten and strangled. Investigators say the killer cut off her hands and poured acid in an attempt to hide her identity.
Hettrick was stabbed in the back, but no attempt was made to hide her identity.
Attorney General John Suthers tells 9Wants to Know that because the Hettrick case is before a grand jury, it prevents him from commenting.
"I've got some good lawyers and investigators and we will follow every since lead. We will have to disprove that some people did it. We have additional DNA evidence that causes us to feel very good about the way this case is moving forward," Suthers said. "It's a matter in front the grand jury and I cannot say anymore."
The FBI had no comment.
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