Actually, one of the things I value about my degrees is that students who have them actually had to earn them. They're not just paper, they represent something real. In my graduate work, we heard on a number of occasions of students who were caught cheating. Some came to light after graduation. I many cases, they rescinded the degree. If you're a Duke student and think you won't get smacked down for this sort of thing, you're wrong. It's the very same reason I'm ticked off at UNC. They demonstrated they're willing to give degrees to anyone who is good at sports.
Duke has nothing to fear from a lawsuit unless they tag someone who didn't actually cheat. If you turned in something that's byte-for-byte identical to something off the interwebz, you deserve, at a minimum, to fail the class.