Torts - Cases, Principles, and Institutions Fifth Edition, 2016a

Witt & Tani, TCPI 6. Causation
simultaneously recognized the difficulty of uncertain defendant cases. However, it gives courts
the flexibility to “decide, based on the availability of evidence and on policy grounds, to modify
or shift the burden of proof for factual cause” in order to cope with these challenging cases. Id.
The Third Restatement’s approach has had a mixed reception. Federal courts have
applied it in interpreting causation in federal statutes. See, e.g., June v. Union Carbide Corp., 577
F.3d 1234, 1239 (10th Cir. 2009) (interpreting causation in Price-Anderson Act). Several states
have cited it generally for the proposition that but-for causality is the default standard of causality.
See, e.g., Thompson v. Kaczinski, 774 N.W.2d 829, 839 (Iowa 2009). However, many states still
use the “substantial factor” analysis in toxic tort cases, without even commenting on the Third
Restatement’s rejection of that language. See, e.g., Betz v. Pneumo Abex LLC, 615 Pa. 504, 524
(2012); Dixon v. Ford Motor Co., 433 Md. 137, 150 (2013).
Judge Calabresi has criticized the Third Restatement approach as being potentially “too
certain.” He asks whether the market share liability doctrine or other creative solutions to recent
problems in tort doctrine would have evolved under the strict but-for test. See Rue, Returning to
the Roots of the Bramble Bush, supra, at 2732. Is the flexibility provided by the inherent
vagueness of the substantial factor test a tool of judicial economy, by giving judges flexibility to
structure new doctrine? Or is it a confusing phrase that leads the law to solve problems best left
to other branches of government?
F. Causation Beyond Torts
Causation is not an issue in torts alone, of course. Courts and legislatures have drawn
heavily on torts principles in developing causation standards in a wide range of fields.
1. The Criminal Law
The paradigmatic example of multiple sufficient causes is captured eloquently by Justice
Antonin Scalia in Burrage v. United States, 134 S. Ct. 881, 890 (2014):
[C]ourts have not always required strict but-for causality, even where criminal
liability is at issue. The most common (though still rare) instance of this occurs
when multiple sufficient causes independently, but concurrently, produce a
result. . . . To illustrate, if “A stabs B, inflicting a fatal wound; while at the same
moment X, acting independently, shoots B in the head . . . also inflicting [a fatal]
wound; and B dies from the combined effects of the two wounds,” A will generally
be liable for homicide even though his conduct was not a but-for cause of B’s death
(since B would have died from X’s actions in any event).
However, the Court does not always deviate from the but-for approach in multiple sufficient
causation cases. Justice Scalia’s opinion in Burrage proceeded to apply the but-for causation test
to a sentencing statute that provided for a higher penalty for drug distribution crimes where death
“results from” the crime. The Court found that the phrase “results from” in the statute required
that the drug offense be a necessary cause of the death and that a defendant convicted of drug
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