In 1806, he denounced the international slave trade as a 'violation of human rights' and called upon Congress to criminalize it. Congress responded by approving the Act Prohibiting Importation of Slaves the following year. Jefferson hoped that his appointments would weaken Chief Justice Marshall's influence on the Court, but, with the partial exception of Johnson, his Supreme Court appointments tended to support Marshall's decisions. Jefferson also appointed seven United States circuit court judges and nine United States district court judges.