COINTELPRO (abbreviation derived from COunter INTELligence PROgram) was a series of covert and, at times, illegal projects conducted by the United States Federal Bureau of Investigation (FBI) aimed at surveilling, infiltrating, discrediting, and disrupting domestic political organizations.
Its targets included various leftist individuals and organizations, notably many associated with the "New Left", which are now often considered very politically correct, so it is intensely disliked by leftist sources such as leftist Wikipedia, which states long and detailed criticisms of it.
Wikipedia states that the FBI has used covert operations against domestic political groups since its inception; however, covert operations under the official COINTELPRO label took place between 1956 and 1971. FBI Director J. Edgar Hoover issued directives governing COINTELPRO, ordering FBI agents to "expose, disrupt, misdirect, discredit, or otherwise neutralize" the activities of these movements and especially their leaders.
See also the article on J. Edgar Hoover on his stated personal use of sensitive information for blackmailing purposes, to gain power for himself and possibly also the FBI, possibly enabling the stated illegal methods used. His death in 1972 coincides with the official end of COINTELPRO.
Wikipedia, however, alleges that "COINTELPRO tactics are still used to this day and have been alleged to include discrediting targets through psychological warfare; smearing individuals and groups using forged documents and by planting false reports in the media; harassment; wrongful imprisonment; and illegal violence, including assassination."
FBI records are stated to show that COINTELPRO resources targeted numerous groups and individuals that the FBI deemed subversive, including, among others, feminist organizations, the Communist Party USA, anti–Vietnam War organizers, activists of the Civil Rights Movement or Black Power movement (e.g. Martin Luther King Jr., the Nation of Islam, and the Black Panther Party), environmentalist and animal rights organizations, Amerindian and Hispanic organizations, independence movements (such as Puerto Rican independence groups), and Ernest Hemingway.
Wikipedia states examples such as "in San Diego, the FBI financed, armed, and controlled an extreme right-wing group of former members of the Minutemen anti-communist para-military organization, transforming it into a group called the Secret Army Organization that targeted groups, activists, and leaders involved in the Anti-War Movement, using both intimidation and violent acts." and "Beginning in 1969, leaders of the Black Panther Party were targeted by the COINTELPRO and "neutralized" by being assassinated, imprisoned, publicly humiliated or falsely charged with crimes. Common tactics used by COINTELPRO were perjury, witness harassment, witness intimidation, and withholding of evidence.""
More recently, variously leftist organizations are stated by leftist Wikipedia to have been unfairly targeted by COINTELPRO-like methods. One stated example is the Black Lives Matter movement.