I know there are some situations where years or even decades later a case is being re-opened due to new advances in technology like DNA testing. I am wondering what the legal mechanism is to do so. My understanding is that there is only a limited time during which a case can be appealed and if that has not occurred that there is no more recourse. And yet, some cases are being reopened and re-tried. What is the term for this legal procedure and what are the steps involved? Thank you