Superseding Cause

A superseding cause is an event or act by someone else, occurring after a defendant's conduct, that is so unexpected or independent that the law treats it as breaking the chain of responsibility. If a jury finds a superseding cause, the earlier defendant is not liable even though its conduct played some part in the harm.

Origin

The concept is part of the common law of proximate cause and has been discussed in tort cases and treatises for well over a century. Modern courts usually ask whether the intervening act was reasonably foreseeable; a foreseeable intervening act generally does not cut off liability.

Significance in Asbestos Context

In asbestos cases, manufacturers sometimes argue that an employer's conduct was a superseding cause: for example, that the employer ignored warnings, failed to provide respirators, or violated safety rules. Plaintiffs respond that unsafe workplaces were exactly the kind of risk a manufacturer should have foreseen, and that a company that never warned cannot blame others for failing to pass on a warning. Courts are often skeptical of the defense where the product itself carried no adequate warning. The argument overlaps with the sophisticated user and learned intermediary doctrines, which also look at who was in a position to protect the worker. Whether it succeeds depends heavily on state law and the facts of the workplace.

Example Sentence

The insulation maker argued that the shipyard's decision to ignore Navy dust-control rules was a superseding cause of the pipefitter's disease, but the court left the question for the jury.

Related Terms

Proximate Cause, Foreseeability, Causation, Sophisticated User Doctrine, Learned Intermediary Doctrine, Failure to Warn

Notes

• Tell your lawyer what safety equipment, training or warnings you received at work, and from whom.
• Old safety rules, union notices or company memos from your workplace can be useful evidence.