Internal Revenue Service, the FCC, and the NLRB, exercises executive power." Notwithstanding Scalia's sharp dissents in landmark separation-of-powers cases such as Mistretta v. United States and Morrison v. Olson, Scalia apparently "describe[d] Freytag as the single worst opinion of his incumbency" on the U.S. Supreme Court. Although the 2008 U.S. government directory of executive and legislative appointed officers ("the Plum Book") categorized the Tax Court as part of the legislative branch, the 2012 revised version removed the Tax Court and listed it under neither the legislative nor the executive branches. Under an amendment to the Internal Revenue Code of 1986 enacted in late 2015, the U.S. Tax Court "is not an agency of, and shall be independent of, the executive branch of the Government." However, section 7443(f) of the Code still provides that a Tax Court judge may be removed by the President "for inefficiency, neglect of duty, or malfeasance in office". Jurisdiction of the Tax Court The Tax Court provides a judicial forum in which affected persons can dispute tax deficiencies determined by the Commissioner of Internal Revenue prior to payment of the disputed amounts. The jurisdiction of the Tax Court includes, but is not limited to the authority to hear: tax disputes concerning notices of deficiency notices of transferee liability certain types of declaratory judgment readjustment and adjustment of partnership items review of the failure to abate interest administrative costs worker classification relief from joint and several liability on a joint return review of certain collection actions Congress amended the Internal Revenue Code, now codified in Internal Revenue Code section 7482, providing that decisions of the Tax Court may be reviewed by the applicable geographical United States Court of Appeals other than the Court of Appeals for the Federal Circuit. (See Article I and Article III tribunals). "Small Tax Cases" are conducted under Internal Revenue Code section 7463, and generally involve only amounts in controversy of $50,000 or less for any one tax year. The "Small Tax Case" procedure is available "at the option of the taxpayer." These cases are neither appealable nor precedential. At times there have been efforts in the Congress and the Tax Bar to create a single national Court of Appeals for tax cases (or make Tax Court decisions appealable to a single existing Court of Appeals), to maintain uniformity in the application of the nation's tax laws (the very reason underlying the creation