Commissioner of Revenue of Massachusetts v. National Private Truck Council, Inc.

reasoning preemption- should not turn on the name a plaintiff gives to his cause of action | the level of deference is less than required under the substantial evidence test, but consideration should be given to the slate hearing panel’s opportunity to observe the demeanor of the witnesses | District Court lacked jurisdiction over employee’s Equal Pay Act claims against United States under the Tucker Act, because claims exceeded jurisdictional limits, thereby requiring action to be brought in Court of Federal Claims