How have courts interpreted the meaning of an amendatory act in the context of statutory construction?

The mere fact of an amendment itself does not indicate that the legislature intended to change a law. It is the duty of a court in construing a statute to consider time and circumstances surrounding the enactment as well as the object to be accomplished by it. United States v. Curtis-Nevada Mines, Inc., 611 F.2d 1277 (9th Cir.1980). This general rule of statutory construction is also applicable to the interpretation of amendatory acts. The original act and the circumstances surrounding its enactment should be considered. Judicial and executive interpretations of the original act should also be considered.