If you're a fan of the CSI shows, you've seen Hollywood's version of the crime lab. A lot of that is ridiculous, of course - instantaneous DNA matches and all - but one thing is consistent. The lab work has to stand up in court. That's why the Metro East Forensic Science lab is investigation a breach of protocol by one of its scientists. That person returned evidence to a police agency with a label error. Officials don't know if it was an isolated incident (error) or if they will find a pattern when they go through his case files. The Commander and Deputy Director were both candid in admitting the mistake and clear that they are working to get to the bottom of it. Humans make mistakes, but with someone's guilt or innocence at stake, there's no room for error.