THE TWIN PROBLEM WITH DNA TESTING

This January thieves made off with over a million dollars of jewelry from a store in Berlin, Germany which happens to be one of the most luxurious department stores in the world. While the miscreants were able to avoid triggering the store’s sophisticated security system, they left behind a critical piece of evidence - a glove. The glove contained DNA material. Recently, the German authorities arrested a suspect with matching DNA characteristics.

There is a rub, however, the suspect has a twin brother. While the most advanced DNA test can distinguish DNA patterns between identical twins, Germany’s rules of criminal procedure will not allow the more advanced test result.

This scientific problem can create a whipsaw defense, where the suspect can claim that his brother was the real culprit. In short, there is a 50/50 chance that the cops got the wrong guy. Is that enough to convict? I doubt it.