This was done based on DNA traces found at the scene of the crimes committed by this unnamed woman suspected of being a serial killer. It turns out now though that the investigators of the crimes may have to accept the fact that it was the swabs used to collect the evidence that were contaminated by an innocent woman – possibly during manufacture of the swabs.
According to prosecutors in the south-western town of Saarbruecken, doubts about the existence of the “phantom killer” were raised when her DNA appeared on documents belonging to a person who had died in a fire.
When police first tried to identify the victim, they found the phantom’s DNA on the dead person’s ID. But in a subsequent test, no trace of the phantom’s DNA could be found on the document.
That was the point at which alarm bells started ringing and investigators began to suspect that the test material itself may have been contaminated with DNA, prosecutors say.
Source: BBC News
Kind of makes one wonder if such a thing has happened before albeit on a smaller scale?