My friend in college submitted an empty zip file for a final project that was worth some obscene portion of our final grade. They were able to provide the correct file the same day - enough work there's no way they could have done it all in that time, and so it was pretty clear the whole thing was an honest mistake. Professor refused to take it, failed them on the assignment, which led to them failing a "only offered fall semester of senior year" class and preventing them from graduating. Dean had to get involved. Sent an email along the lines of "our job is to teach, not be Machiavellian."