Morales v. Mack Trucks, Inc.

stating that “where the application of res judicata rules does not touch upon an important question of state law such as privity, we will apply federal rules of decision to measure the preclusive effect of the judgment” | change in theory or measure of relief does not create a new claim | change in theory or measure of relief does not create a new claim | “An exception to the general principle that lack of knowledge will not avoid the application of res judicata rules is found in cases where fraud, concealment, or misrepresentation have caused the plaintiff to fail to include a claim in a former action.”