Well, it should have.

What you're telling us is that you failed the fellow because he failed to turn in 3 assignments. He then said he did turn them in, which was proven false.

You and your boss then decided to upgrade him to a 'D', because of a completely unrelated issue that he may have misinterpreted your definition of what would 'probably' fail him. Except he lied about it anyway. How could the lie NOT come up...it was the first thing you mentioned here!!

That's great. I don't know what the subject of the course is, but hope that all those who DID submit all 3 assignments (or even 1 or 2) were graded just as generously.

Nothing personal mind you...I'm just interpreting your post & really can't get around that deliberate lie, assuming the computer records can truly be depended upon. If he said he submitted the assignments when he knew he didn't...then it's because he KNEW he would 'probably' fail for not submitting them. Otherwise, why would he bother to lie about it??? He could just say, "You didn't say we would DEFINITELY fail for not turning them in, you only said we would PROBABLY fail! What about all my other work?"

Oh, well...no skin off my nose. Can't wait to read what happens next.