P incurred expenses of $550,159.78 in connection with the confirmation hearings on being Vice President in 1974, primarily for legal and other professional services. P asserted that the entire amount of $550,159.78 was deductible as expenses of the trade or business of 'performing the functions of public office.' To substantiate his claim P submitted the following evidence. P served as Governor of New York State between January 1959 and December 1973, when he resigned to devote his full time to the Commission on Critical Choices for Americans (1973-74) and the National Commission on Water Quality (1973-74), as showing the trade or business in which P had engaged. P also held positions as Coordinator of Inter-American Affairs (1940-44), Assistant Secretary of State for American Republic Affairs (1944-45), Chairman of the Presidential Advisory Board on International Development (1950-51), Undersecretary of Health, Education, and Welfare (1953-54), and Special Assistant to the President for International Affairs (1954-55). Commissioner (D) denied the deductions and the Tax Court affirmed. P appealed.