Overall, COINTELPRO encompassed disruption and sabotage of the Socialist Workers Party (1961), the Ku Klux Klan (1964), the Nation of Islam, the Black Panther Party (1967), and the entire New Left social/political movement, which included antiwar, community, and religious groups (1968). A later investigation by the Senate's Church Committee (see below) stated that "COINTELPRO began in 1956, in part because of frustration with Supreme Court rulings limiting the Government's power to proceed overtly against dissident groups." Official congressional committees and several court cases have concluded that COINTELPRO operations against communist and socialist groups exceeded statutory limits on FBI activity and violated constitutional guarantees of freedom of speech and association.