Intelligence Agency (CIA) and the Federal Bureau of Investigation (FBI), popularly known as the Church Committee.

By then, the North was facing the final crisis leading up to its defeat in the Vietnam war in April with the capture of the former southern capital of that nation, Saigon, by the North Vietnamese army and the subsequent flight of the last U.S. troops and officials.

The legislative initiative was favored by the formidable domestic anti-war movement and denunciation of Washington's interventionist policy. But few could have imagined that the results of the committee's investigations would unveil assassination plots against Cuba's top leader Fidel Castro, some of which were denounced by the Cuban authorities and dismissed by the U.S. government as "communist propaganda".

The Church Committee brought to light from the CIA's veil of secrecy chemical engineer Sidney Gottlieb (1918-1999), at the center of the sinister plans against Fidel Castro's life from his position as head of the CIA's Technical Services Division for more than 15 years and who hired sorceresses to predict the future and practitioners of satanic rites to implicate the devil in the success of his operations, among other extravagant ways of wasting the taxpayers' money.

However, his legacy was not always so extravagant and he left as his masterpiece "Study of Assassinations", declassified in the 1990s, with instructions about how to accurately stab a dagger in the carotid area or the heart, shoot at someone’s head, make a murder look like an accident by electrocution, throw a body from a rooftop, and the use of poisons, among other lessons taught to several generations of CIA officers.

During his active career in that agency until the 1970s he had the full support of the White House and a large budget that allowed him complete freedom to devote himself to his criminal programs.

From the beginning of the operations against Cuba, his obsession would be to destroy the Revolution and above all to kill Fidel. In 1960 an operation was planned to simulate the appearance of Christ in front of the Havana seawall by means of fireworks and lights projected by a submarine to call for an insurrection led by the god made by the CIA’s special effects.

He proposed in 1960-61 to put thallium in the Cuban leader's shoes to cause his beard to fall off and reduce his charisma, or to introduce LSD in a Cuban TV studio where he appeared to cause strange behaviors in and deprive people from any self-control.

Also known as Dr. Death, he planned to kill the Commander in Chief with poisoned pills diluted in drinks, syringes with lethal viruses, cigars with killer bacteria and attempts to hide an explosive charge in a shell on the seabed in the spots of the Island where the Cuban leader used to spearfish. He also devised the inoculation of a diving suit with a bacterium that produces death after weeks of agony, during which the body gradually decomposes.

He experimented during the Viet Nam war on prisoners whose skulls were cut open to install electrodes and radio antennas to control them through CIA electronic signals as part of Operation MK Ultra, also reported by the committee.

The Church Committee reports revealed that the CIA also used more conventional means in conjunction with Cuban counterrevolutionaries and the U.S. Mafia to assassinate the Cuban leader with high-powered rifles and terrorist actions. Many of these plans date back to Operation Mongoose approved in late 1961 by President John F. Kennedy to avenge the Bay of Pigs defeat and ended after the October Crisis.

It was also recognized that the agency was involved in the assassinations in 1960 of Congo president Patrice Lumumba, who opposed colonial interests; Rafael Leonidas Trujillo in 1961, dictator of the Dominican Republic and a hindrance to U.S. policy in the region; and General Rene Schneider, head of the Chilean armed forces opposed to a coup d'état and assassinated in 1970.

The committee investigated the assassination of J. F. Kennedy and concluded that the official inquiries by the Warren Committee had significant errors and that senior intelligence officials involved in the investigations apparently concealed relevant information.

After 1975, when the results of the Church Committee investigations became known, several U.S. administrations issued laws prohibiting their intelligence services from getting involved in assassinations against foreign leaders and personalities.

The work of the Church Committee also shed light on the aggressive and genocidal essence of Yankee imperialism against Cuba with complete disregard for the law. Investigations by Cuban specialists reveal more than 600 assassination attempts and plans to kill Fidel long after the denunciations of that institution were known and practically until his decease in 2016.