Hallet's plan for the Capitol was a favourite in the design competition put out by Secretary of State Thomas Jefferson in the spring of 1792. However, it was deemed too costly and ornamental and was ultimately rejected in favour of a classical design by William Thornton. Hallet was appointed, along with James Hoban, to review Thornton's plans and oversee construction. He suggested many substantial changes to Thornton's design, and modified the plan for the east front, before being dismissed in November 1794.