4 U.S.C. § 113: Residence of Members of Congress for State income tax laws

treat such Member as a resident or domiciliary of such State or political subdivision thereof; or treat any compensation paid by the United States to such Member as income for services performed within, or from sources within, such State or political subdivision thereof, the term “Member of Congress” includes the delegates from the District of Columbia, Guam, and the Virgin Islands, and the Resident Commissioner from Puerto Rico; and the term “State” includes the District of Columbia. No State, or political subdivision thereof, in which a Member of Congress maintains a place of abode for purposes of attending sessions of Congress may impose a personal property tax with respect to any motor vehicle owned by such Member (or by the spouse of such Member) unless such Member represents such State or a district in such State. the term ‘Member of Congress’ includes the delegates from the District of Columbia, Guam, and the Virgin Islands, and the Resident Commissioner from Puerto Rico; the term ‘State’ includes the District of Columbia; and the term ‘personal property tax’ means any tax imposed on an annual basis and levied on, with respect to, or measured by, the market value or assessed value of an item of personal property. This section shall apply to all taxable periods beginning on or after January 1, 1985 .”