A couple of years ago, a 28-year-old man ran into trouble in the scenic Brenta River near Padova, Italy. Witnesses saw him struggling in the water; soon after, he drowned.
When Stefano Vanin, a forensic scientist at the University of Huddersfield in Great Britain, analyzed the body, the unfortunate man showed no signs of injury on the body but for some small abrasions around the eye. Vanin, who's studied entomology, realized that the marks were caused by an eyeless crustacean called Niphargus elegans that had started eating away at the corpse. But a less careful analyst might have concluded they were signs of injury, and that the man's death involved foul play.
Vanin has been studying cases like this in an attempt to figure out all of the ways in which little critters can affect a crime scene and throw off an investigation. Ants, for instance, can apparently leave marks on a corpse's face that look like a punch. Forensic scientists apparently have a lot more to learn: Vanin and his colleague report that their study of the drowning victim, published in Forensic Science International last year, was the first to look at post-mortem lesions caused freshwater organisms. Hopefully investigators will heed the new findings and make sure that bugs don't get any more people convicted for crimes they didn't commit.