Richard Nixon actually said...
it is hereby ordered that any income, excess-profits, estate, or gift tax return for the years 1948 to 1969, inclusive, shall, during the Ninety-first Congress, be open to inspection by the Senate Committee on Government Operations or any duly authorized subcommittee thereof
Context
Executive Order 11454—Inspection of Income, Excess-Profits, Estate, and Gift Tax Returns by the Senate Committee on...
02/06/1969