you could always check for plagiarism the old-fashioned way, by running distinct phrases through google.... It's not perfect, but it'll rule out most problems, and then you can give a grade with a clear conscience.<br>
<br>in a way, isn't there a class-based concern here? rich students can afford to buy a unique paper, written just for them, and therefore won't get caught, while poor students who want to cheat can only afford public papers or their friends'. Unfair, somehow.<br>
<br>Kate<br><br><br><br>