Hacker News new | ask | show | jobs
by runarb 4704 days ago
Reminds me of "the Phantom of Heilbronn", and alleged female serial killer the German police used DNA to link to more than 40 crimes. It baffled the investigators for more than two years until they found out that the DNA was from pollutions in the cotton swabs used for collecting DNA samples.

More: http://en.wikipedia.org/wiki/Phantom_of_Heilbronn