Normally a plaintiff must show that it is more likely than not that her injuries were caused by the defendant. (Preponderance of evidence)

An exception is made in some cases. It may be enough that the plaintiff shows a substantial likelihood that her injuries were caused by the defendant. (Substantial factor test). This is very helpful in medical malpractice cases or when two or more causes combine to cause a single injury--like the two negligently set fires that combine to burn down a house.

But a 2% chance would not be a substantial likelihood.

Link back to problem 5.