Thomas Jefferson's clearest statement on executive prerogative can be found in his letter to John B. Colvin. Although this letter has been cited often, few scholars have considered its argument in its entirety, and no scholar has yet considered its context. By reexamining the letter, this article presents Jefferson's understanding of the prerogative power, which argues that the president must act outside the law when self-preservation or the public good requires but must then declare his action to Congress or the people. Because Jefferson's understanding both expands and demarcates prerogative, it can contribute to the scholarly debate on prerogative.