Harvard Law School’s Private Law Workshop: John C. Harrison, Immunity Rules

Post by Samuel Beswick, Frank Knox Memorial Fellow, SJD candidate, Harvard Law School

In the third of our trilogy of sessions on Hohfeld, Professor Harrison this week presented to the HLS Private Law Workshop a view of Calabresi and Melamed’s famous Cathedral article through a Hohfeldian lens. Calabresi and Melamed organized legal entitlements into three types: those protected by property rules, those protected by liability rules, and inalienable entitlements. An entitlement is protected by a liability rule when, if it is interfered with, the law requires only that the defendant pay an objectively determined value for it (generally in the form of compensatory damages).

Liability rules, Harrison contends, are “a false category.” Calabresi and Melamed had taken accident law from tort and eminent domain from the law of property, and grouped the two as examples of “instances in which society uses liability rules.” But their typology obscured the analytically distinct nature of these categories in two ways: by conflating rules about right/duty and rules about power/liability; and by conflating substantive law and remedies.

In negligence law, for example, the claimant has a right to be free from—and the defendant a duty to avoid—negligent harm. That right is further protected by an immunity from others’ interference: a negligence defendant is not, of her own accord, able to alter legal relations so as to divest the right-holder of her right against being carelessly injured. To use Harrison’s phrase: “committing a tort does not change primary duties or rights.”

By contrast, the state exercising its power of eminent domain does have a (unique) power to alter a claimant’s legal position by acquiring an interest in, or purchasing, the claimant’s property. Private owners in such cases do not have immunity protection from government interference with their legal entitlements. The power of eminent domain changes the claimant’s primary rights.

Torts are not takings; they do not affect primary legal relations. And while compensatory remedies in both accident law and eminent domain are facially similar, they are conceptually and practically distinct. A careful analysis of Calabresi and Melamed thus offers lessons not only about liabilities, but about powers and immunities.