<prompt> Human: Is there a huge legality issue or should I roll with the flow, not to be the biggest shit bag ever.  <response>: Contact your bank. Tell them.They will most-likely deal with it. If you are really being good, contact the person or organization that gave you the check and warn them that this happened. Super worst case scenario you might owe them a small returned-check fee.Mistakes happen. Dealing with the aftermath in a professional and mature manner is the difference between a child and an adult. 