Via Business Insider:
How can we stop such trends toward dishonesty (in this case, broader acceptance of illegal downloading)? The problem is that if someone has acquired 97% of their music illegally, why would they legally buy the next 1%? Would they do it in order to be 4% legal? It turns out that we view ourselves categorically as either good or bad, and moving from being 3% legal to being 4% legal is not a very compelling motivation.
This is where confession and amnesty can come into play. What we find in our experiments is that once we start thinking of ourselves as polluted, there is not much incentive to behave well, and the trip down the slippery slope is likely. This is the bad news. The good news is that in such cases, confession, where we articulate what we have done wrong, is an incredibly effective mechanism for resetting our moral compass.
Religious folks call that atonement.