General Principles of International Law for Apportioning Responsibility

I have received a significant amount of feedback on my previous post on apportioning responsibility for international violations and therefore I wanted to do a couple of follow up posts on the subject. As Judge Simma indicated in his Separate Opinion in the Oil Platforms case, there arguably is a general principle of international law that joint tortfeasors are jointly and severally liable. But how large a consensus? It depends on the circumstances.

There is no comprehensive analysis of domestic tort laws on this question. However, preliminary research regarding the practice in almost two dozen countries suggests that joint and several liability is the accepted standard for apportioning liability, at least when the defendants are acting in concert. The practice is sufficiently consistent that one can accurately describe it as a general principle of law, embodied in the major systems of the world.

What is far less clear from a comparative analysis is whether joint and several liability is the accepted standard when multiple tortfeasors are not acting in concert. In undertaking his analysis of American law, Judge Simma relied on the Restatement (Second) of Torts and the famous case of Summers v. Tice to support his conclusions regarding joint and several liability. But he ignored the Restatement (Third) of Torts published three years before his Separate Opinion in Oil Platforms. The most recent Restatement concludes that “there is currently no majority rule” on the question of liability for independent tortious conduct of multiple tortfeasors who cause an indivisible harm. Instead, the Restatement presents five independent tracks for apportioning liability: (1) joint and several liability; (2) several liability; (3) joint and several liability with reallocation; (4) hybrid liability based on a threshold percentage of comparative responsibility; and (5) hybrid liability based on the type of damages. These different tracks reflect different approaches adopted by the fifty States, which take a number of factors into account, including allocating the risk of a tortfeasor’s insolvency or immunity, the relevance of the plaintiff’s comparative responsibility, the degree of fault among joint tortfeasors, and the type of harm caused by the tortious conduct. Significantly, the approach suggested by Judge Simma—that of pure joint and several liability—is embraced by less than one-third of the jurisdictions in the United States, fewer jurisdictions than the number that employ pure several liability.

Other countries also employ several liability for independent actions of multiple tortfeasors. For example, China utilizes joint and several liability for joint action, but otherwise each tortfeasor who commits independent acts will “bear corresponding compensation liabilities respectively in appropriate proportion to the extent of their faults….” New Zealand has a similar approach, applying joint and several liability for the joint action, but several liability where “there is a coincidence of separate acts that by their conjoined effect cause damage.” If two tortfeasors act independently of one another, then each is liable only for that portion of the damage caused. Israel also has adopted joint and several liability where tortfeasors act in concert, but several liability where there is independent action. “The general rule is that tort liability is individual: every tortfeasor is held liable for the damage caused by his own person.”

These disparate approaches suggest that there is no settled standard for apportioning liability for independent acts of multiple tortfeasors. One comparative scholar surveyed the laws of fifteen countries and concluded that an appropriate standard would impose several liability for independent tortfeasors who cause divisible harm, but joint and several liability where they cause indivisible harm.

This approach of using general principles of international law is most apropos for international courts and tribunals apportioning responsibility for violations involving non-State entities. My next post will address the private international law approach that the courts in the United States will likely use to apportion liability for international law violations.