Executive Order 5321—Inspection of Tax Returns by Department of Commerce for Statistical Purposes
Pursuant to the provisions of section 55 of the Revenue Act of 1928, and section 257 of the Revenue Act of 1926, it is hereby ordered that returns may be open to inspection by officers and employees of the Department of Commerce, for statistical purposes, in accordance and upon compliance with the amendment, bearing even date herewith, to the rules and regulations prescribed by the Secretary of the Treasury and approved by the President, bearing date of April 13, 1926, as amended.
The White House,
April 8, 1930.
Herbert Hoover, Executive Order 5321—Inspection of Tax Returns by Department of Commerce for Statistical Purposes Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/361117