After being ravaged by smallpox, and pressed by increasingly violent land-hungry settlers, the Cherokee adopted a whiteman's form of government in an effort to retain their lands. They established a governmental system modeled on that of the United States, with an elected principal chief, senate, and house of representatives. On April 10, 1810 the seven Cherokee clans met and began the abolition of blood vengeance by giving the sacred duty to the new Cherokee National government. Clans formally relinquished judicial responsibilities by the 1820s when the Cherokee Supreme Court was established. In 1825, the National Council extended citizenship to the children of Cherokee men married to white women. These ideas were largely incorporated into the 1827 Cherokee constitution.[29] The constitution stated that "No person who is of negro or mulatlo [sic] parentage, either by the father or mother side, shall be eligible to hold any office of profit, honor or trust under this Government," with an exception for, "negroes and descendants of white and Indian men by negro women who may have been set free."[30] This definition to limit rights of multiracial descendants, may have been more widely held among the elite than the general population.[31]