The following passages are adapted from articles recently published in North American law review journals.

Passage A

In Canadian and United States common law, blackmail is unique among major crimes: no one has yet adequately explained why it ought to be illegal. The heart of the problem—known as the blackmail paradox—is that two acts, each of which is legally permissible separately, become illegal when combined. If I threaten to expose a criminal act or embarrassing private information unless I am paid money, I have committed blackmail. But the right to free speech protects my right to make such a disclosure, and, in many circumstances, I have a legal right to seek money. So why is it illegal to combine them?

The lack of a successful theory of blackmail has damaging consequences: drawing a clear line between legal and illegal acts has proved impossible without one. Consequently, most blackmail statutes broadly prohibit behavior that no one really believes is criminal and rely on the good judgment of prosecutors not to enforce relevant statutes precisely as written.

It is possible, however, to articulate a coherent theory of blackmail. The key to the wrongness of the blackmail transaction is its triangular structure. The blackmailer obtains what he wants by using a supplementary leverage, leverage that depends upon a third party. The blackmail victim pays to avoid being harmed by persons other than the blackmailer. For example, when a blackmailer threatens to turn in a criminal unless paid money, the blackmailer is bargaining with the state's chip. Thus, blackmail is criminal because it involves the misuse of a third party for the blackmailer's own benefit.

Passage B

Classical Roman law had no special category for blackmail; it was not necessary. Roman jurists began their evaluation of specific categories of actions by considering whether the action caused harm, not by considering the legality or illegality of the action itself.

Their assumption—true enough, it seems—was that a victim of blackmail would be harmed if shameful but private information were revealed to the world. And if the shame would cause harm to the person's status or reputation, then prima facie the threatened act of revelation was unlawful. The burden of proof shifted to the possessor of the information: the party who had or threatened to reveal shameful facts had to show positive cause for the privilege of revealing the information.

In short, assertion of the truth of the shameful fact being revealed was not, in itself, sufficient to constitute a legal privilege. Granted, truth was not wholly irrelevant; false disclosures were granted even less protection than true ones. But even if it were true, the revelation of shameful information was protected only if the revelation had been made for a legitimate purpose and dealt with a matter that the public authorities had an interest in having revealed. Just because something shameful happened to be true did not mean it was lawful to reveal it.