48 U.S.C. § 891

The qualified electors of Puerto Rico shall choose a Resident Commissioner to the United States at each general election, whose term of office shall be four years from the 3d of January following such general election, and who shall be entitled to receive official recognition as such commissioner by all of the departments of the Government of the United States, upon presentation, through the Department of State, of a certificate of election of the Governor of Puerto Rico.