US CONSTITUTION AMENDMENT 14 https://constitution.congress.gov/constitution/amendment-14/

Section 3: No Person shall be a Senator or Representative in Congress or elector of President and Vice-President, or hold any office, shall have engaged in insurrection or rebellion against the same

Section 4: But neither the United States nor any State shall assume or pay any debt or obligation incurred in aid of insurrection or rebellion against the United States