The primary source document described below, which can be viewed by clicking the thumbnail at right, is part of a 1,434-page file on César Chávez and the farmworker movement compiled by the Federal Bureau of Investigation (FBI) between 1965 and 1973. The FBI's surveillance of Chávez, which paralleled larger efforts to prove that protest groups of the civil rights era had been infiltrated by subversive influences, was unable to uncover any evidence of communism or corruption in the activities of Chávez and his followers.

The FBI's dossier on Chávez was obtained under the Freedom of Information Act (FOIA), which contains provisions that allowed the FBI to withhold portions of the documents from public view. Indeed, many parts—and in some cases, entire pages—have been excised from the files. Nevertheless, the collection provides a compelling window into the efforts of the farmworker movement, as well as the values and methods of the FBI itself.

From 1967 to 1968, the Federal Bureau of Investigation (FBI) collected information related to farm worker strikes near Rio Grande City, Texas. Launched in May 1966, the protests were organized by National Farm Workers Association (NFWA), which merged with the United Farm Workers Organizing Committee (UFWOC) as it led the Delano Grape Strike in California. During July 4 to September 5, 1966, about 100 people participated in a march to Austin to protest the low wages and living conditions of farm laborers. As demonstrations continued in 1967, the UFWOC accused the Texas Rangers and local law enforcement of unlawful arrests of picketers. The strikes received additional media attention as the Senate Sub-Committee on Migratory Labor held hearings in Rio Grande City on June 28-29, 1967.

Sent by the San Antonio field office to FBI headquarters in Washington, D.C., several documents dated from June to September 1967 refer to articles from local newspapers that describe the march to Austin, union allegations of civil rights violations, and the Senate subcommittee hearings.

A June 21, 1967, memo by the Los Angeles field office confirmed findings by the San Antonio field office that four leaders of the Rio Grande Valley protests had been involved in the Delano Grape Strike.

At the request of the White House, the FBI compiled a memo dated on July 7, 1967, which provided background on the situation in Rio Grande City, communist influences in the strike, and its links to the Delano Grape Strike.

On September 1 and 5, the San Antonio field office provided information on union rallies held in New Braunfels and Austin that included a couple hundred people.

Sent by the San Antonio field office, a teletype dated on Sept. 29, 1967, and subsequent documents, include reports of picketing by migrant worker supporters during President Lyndon Johnson's address at the National Legislative Conference in San Antonio.