For researchers, bad data can be scary and a real damage, and that is no joke.  Nevertheless, needing to consult data that has been classified as bad, doesn’t need to feel quite as dangerous as depicted in this Don Mayne cartoon.  Institutions and research groups should have codified operational procedures for handling of bad data and how to ensure that is does not have serious consequences (such as the bad data leaking and infecting the rest of the research data).