In the early hours of November 30th, 2012, police responded to an emergency call from a house in Monteserrano in Silicon Valley.

Some men had broken into the house and tied up the owner, Ravich Kumar, and his ex-wife, Haryndor.

Then the intruder started searching for valuables.

After they'd left,

Haryndor managed to free herself and call 911, but Ravis was declared dead at the scene. He'd suffocated after being gagged with duct tape. Investigators went over the house carefully, looking for evidence,

but the intruders had made a concerted effort not to leave any fingerprints

or DNA.

They'd worn latex gloves and had washed the insides of them with soapy water before discarding

them.

But the investigators did manage to find DNA at the crime scene, including some under the victim's

fingernails.

And when the DNA samples were run through the California State DNA database, it produced three matches.

We're used to thinking that if a DNA match has been found, then it's an open and shut case.

Surely that's the end of the story. But in this case, it was just the beginning.

If there's DNA evidence in a case, people just generally feel like, well, it's said and done.

It's like, we figured it out. We solved the case.

This is Katie Worth, a PBS reporter who covered the story.

Unlike most forensic evidence, DNA evidence is actually based on science and came from the world of science.

That's the closest thing that we can come to like a truth serum, you know.

However, that doesn't mean that DNA evidence is infallible.

These three DNA matches found at the crime scene in Monteserrano were from three men who all lived nearby in the Bay Area.

DNA from one of them, DiAngelo Austin, was found on the duct tape.

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