The facts in this case involve medical malpractice but the ruling has ramifications beyond medical malpractice. It is instructive as to multiple causes, i.e. “but for” v. “substantial factor” standards, and legal (proximate) causation v. cause-in-fact.
“…we conclude that the traditional but-for factual causation standard is the appropriate standard to be employed in most cases, including those involving multiple alleged causes.“