Imagine someone named Sue finds herself in possession of some information about Bob that he would prefer she not reveal to anyone else. So she offers him a deal: “Pay me $10,000 and I’ll keep my mouth shut.” Is that wrong?
Most people intuitively feel the answer is yes. But it’s surprisingly tricky to explain, in a coherent, consistent manner, why that should be the case. The paradox of blackmail has bedeviled legal scholars and philosophers of law for years: while it’s typically legal to reveal information about someone, as long as that information is accurate and legally-obtained, it’s illegal to threaten to do so as a way of soliciting money from him.
Unlike with extortion, where the perpetrator is threatening to do something illegal if she isn’t paid (e.g., “Give me $10,000 or I’ll burn down your house”), with blackmail the perpetrator is threatening to do something legal. If the act itself – revealing the information – isn’t bad enough to be criminalized, then why is merely threatening to commit the act so terrible?
This paradox is often expressed in terms of blackmail being a criminal act composed entirely of uncriminal parts. Telling someone you'd like $10,000 isn’t a crime; revealing someone’s secret isn’t a crime; and yet, telling someone you'd either like $10,000 or you're going to reveal his secret is a crime. How can that be?
Some scholars have countered that there is no logical reason to think that several unobjectionable parts can't add up to an objectionable whole. Philosopher Saul Smilansky, in the book 10 Moral Paradoxes, makes this case using the examples of bigamy and prostitution: It’s legal to marry one woman, and it’s legal to marry another woman, but it’s not legal to marry both. It’s legal to give someone money, and it’s legal to have sex, but it’s not legal to give someone money for sex. Blackmail may not be a complete aberration.
However, Smilansky acknowledges, even if there's no contradiction entailed by blackmail being illegal despite its component parts all being legal, we still need some explanation for why this particular combination of parts produces an objectionable result. He writes, “The way in which the ‘alchemy’ of the novel emergence of badness or wrongness operates in ‘ordinary blackmail’ remains mysterious… If one may threaten to do what one is (otherwise) allowed to do, offering not to so act in return for monetary compensation does not seem capable of bringing forth the sense of radical and novel heinousness that blackmail arouses.”
