An understanding of the Assimilative Crimes Act is necessary for any attorney who may one day find himself defending a client who has allegedly committed a criminal offense in an area under federal jurisdiction. At first blush, the lawyer may think that his client is clearly guilty and plan his defense around the creation of a reasonable doubt in the court's or jury's mind. However, in some instances, steps may be taken prior to a defense on the merits which would raise serious doubts as to the legality of the prosecution, and even if a conviction is forthcoming, objections might also be validly raised against the severity of the punishment offered for the offense. It is in this light that the functions and limitations of the ACA will be examined to the end that Congress should adopt a comprehensive criminal code to be applied uniformly to all areas under federal control.