One of my colleagues was teaching an introductory programming course this past spring. He discovered several students cheating by taking code from a public GitHub repository, which contained all the answers for this class. This repository already had an issue opened on it by a professor from another large school, who requested that it be taken down because his students were using it to cheat. No response.
Fortunately, the student left some identifying information in the comments, which we were able to use to determine that he attends our school, in our department. We attempted to contact him to request that he remove the offending code--unfortunately, emails to both his departmental email and his GitHub email went unanswered.
The department has a student code of conduct which states that students must take "all reasonable precautions" to prevent others from using their work. While this student is clearly in violation of that, we can't exactly fail him out of a course he passed over a year ago, and failing him out of course he's currently taking seems petty.
We've considered escalating this to the department, but we're not sure if the department can actually do anything about this. Can a department in the US punish a student for helping other students cheat even if the student is not taking the class where the cheating is occurring? If so, what should be done? If not, might there be anyone at the school that can do anything? This is a large, public state school.