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Clinton Jencks papers

Identifier: COU:869

Scope and Contents

The Clinton Jencks Collection (1886-2002) contains materials about the Western Federation of Miners (WFM) and the International Union of Mine, Mill, and Smelter Workers (IUMMSW). In addition to the WFM/IUMMSW materials, the collection contains materials about Clinton Jencks’ involvement with the IUMMSW, the Jencks Case, and his academic career at San Diego State University.

If your research is specifically about Clinton Jencks, materials about him will be found in: Section I—Personal; Section III—Local Unions—Locals 890, 915 and 929; and in Section VI—Court Cases—Conspiracy Cases—U.S. v Jencks.

The rest of the Clinton Jencks Collection consists of other WFM/IUMMSW materials.

The Clinton Jencks Collection has been organized in the following manner:

I. Personal—includes autobiography, biographical notes, articles and books by/about Jencks, FBI files, histories of WFM and IUMMSW, interviews with Jencks, and testimony to HUAC, 1959.

II. Constitutions of WFM and IUMMSW, 1893-1965.

III. Local Unions and Ladies Auxiliaries, 1892-1966—includes Charter Book of Local Union 1893-, Active Local Unions 1945-1962, and financial records of, 1900-1902, 1949-1955.

IV. Convention Proceedings of WFM and IUMMSW, 1900-1967—includes Canadian Convention Proceedings, 1944, 1949, 1954-1959, 1961, 1963.

V. Executive Board Minutes of WFM and IUMMSW, 1902-1966—includes Canadian Executive Board minutes, 1959-1960

VI. Court Cases 1. Charles H. Moyer v Peabody et al, 1904- 2. William D. Haywood, Charles H. Moyer, and George A. Pettibone v Japser C. Nichols, 1906 3. Idaho v Haywood, Moyer, and Pettibone, 1907 4. Haywood v U.S., 1920 5. Conspiracy Cases a. U.S. v Jencks, 1953 b. U.S. v Maurice E. Travis, 1954 c. Subversive Activities Control Board 1. Herbert Brownell, Jr. v IUMMSW, 1955 2. William P. Rogers v IUMMSW, 1961 3. Robert F. Kennedy v IUMMSW, 1961 d. U.S. v Albert Pezzati et al, 1957 e. U.S. v Raymond Dennis et al, 1961 f. IUMMSW materials concerning Conspiracy Cases

VII. General Files, 1886-1993—includes bargaining, finances, IWW, Mine-Mill Research Department, Mine-Mill Staff Bulletin, Miners’ Magazine, Organizational Summaries, political action, strikes, WFM, etc.

VIII. Audio/Visual Materials—includes cassette tapes, film strips, microfilm, a movie, photographs, and video cassettes.

IX. Oversize—includes bound and unbound magazines and newspapers (including Miners’ Magazine), one photograph printed from Salt of the Earth & Referendum Tally Sheets.


  • Creation: 1934 - 2001

Conditions Governing Access

This collection is open for access.

Conditions Governing Use

Limited duplication of materials allowed for research purposes. User is responsible for all copyright compliance.

Biographical Note

Clinton Jencks (1918-2005) was mineworker, union official for the International Union of Mine, Mill, and Smelt workers, and professor. Born in Colorado Springs, Jencks became interested in mining early and researched mining strikes and labor issues in his local library as a child. Jencks attended the University of Colorado Boulder and became active in the American Student Union, Student League for Industrial Democracy, and Young Communist League. Of these, he was most active in the Young Communist League. These experiences fueled interests in peace, equality, and civil rights. For example, the American Student Union led mixed race group to businesses near campus during that served blacks for the first time.

After graduating in 1939, Jencks moved to St. Louis, organized the St. Louis Inter-Faith Youth Council and the St. Louis Youth Council. As chairman of the Youth Council he met President and Mrs. Roosevelt in the White House in 1939 and 1940. While in St. Louis, he trained for the Air Force and married Virginia Derr in 1942. As an Air Force navigator, he was commissioned Second Lieutenant and sent to the Pacific. There he flew forty missions as lead navigator for his squadron. Jencks was awarded six Air Medals and the Distinguished Flying Cross for his service.

In December 1945, the Jencks, with daughter Linda and son Clinton Michael, moved to Denver. Initially, he worked for Continental Airlines under the G.I Bill. Afterwards he worked an acid plant operator at the American Smelting and Refining Company’s Globe Smelter in north Denver. Jencks joined Local 557 of the International Union of Mine, Mill, and Smelter Workers (IUMMSW), commonly referred to as the Mine-Mill Union. He was elected shop steward for his local union and, in early 1947, the IUMMSW asked him to consider working full-time as the local union representative and organizer for the five locals in the Silver City mining district of southwestern New Mexico.

Originally, five local IUMMSW unions represented Silver City in southwestern New Mexico but the IUMMSW consolidated into a single union for the area locating the union hall in Bayard, New Mexico. The workers at the mines, mills, and smelter were mostly Mexican American. At the time, there were dual wage scales for Mexican Americans and Anglos, segregated housing, segregated theatres, and segregated restaurants. On January 1, 1948, Clinton Jencks was elected president of the Amalgamated Bayard District Union of Mine, Mill and Smelter Workers, Local 890. The workers gave him the nickname “El Palomino.”

After his election to a second term as president in 1950, the IUMMSW requested Jencks serve as an international representative. He split time between Local 890 and the International Union, while Local 890 union attempted to get Mexican American members the same wages and working conditions that other hard-rock miners enjoyed. Jencks led Local 890 to strike the New Jersey Zinc Company’s Empire Zinc Mine near Hanover, New Mexico starting in 1950.

For two winters, strikers experienced arrests and tear gas while relying upon other unionists and progressives for food and clothing. Their wives and children joined them on the picket line. The Empire Zinc Company ended the strike in January 1952 resulting in wage increases, collar-to-collar pay, pensions, company-paid life insurance, and a sickness and accident program. The victory meant a big stride forward in the long struggle for economic, political, and social equality.

Concurrently, national anticommunist hysteria led to the U.S. House Un-American Activities Committee (HUAC) investigations of communist influence in the movie industry. The HUAC blacklisted screenwriters Herbert Biberman and Paul Jarrico. They became part of the Independent Productions Corporation. While on a family vacation in New Mexico, Jarrico heard of the mining strike, finding it interesting because of Mexican Americans demanding the same wages and benefits as white miners and the inclusion of women and children in the strike. Michael Wilson, Jarrico’s brother-in-law, wrote the screenplay.

Production of the film titled “Salt of the Earth” began in January 1953. Mexican actress Rosaura Revueltas arrived in Silver City to play the role of miner “Ramon’s” wife. Juan Chacon, the newly elected president of Local 890, played “Ramon,” and Herbert Biberman directed. During the filming, public sentiment turned against the blacklisted film makers resulting in vandalism and attacks against those involved in the film. Immigration and Naturalization Service officials deported Rosaura Revueltas to Mexico, someone fired shots into Clinton Jencks’ parked car, and the sheriff called the state police to keep the peace so the movie crew could finish filming. The film crew left by March 7, but shortly afterward Local 890’s union hall and the home of the local’s only other white officer was burned. “Salt of the Earth” premiered in New York on March 14, 1954.

For years, the IUMMSW had been suspected of communist influence. The Taft-Hartley Act required all union officials to sign a non-communist affidavit. If a union official had been a member of the Communist Party, but had terminated membership before signing the Taft-Hartley affidavit, this would comply with the act. But if a union official had signed the Taft-Hartley affidavit and if later that same union official was found to be a member of the Communist Party, this was perjury.

In 1949, the Congress of Industrial Organizations (CIO) rejected the IUMMSW for alleged communist influence. In October 1952, Senator McCarran opened hearings in Salt Lake City, Utah, to investigate the union officials in the IUMMSW. Clinton Jencks and other top IUMMSW officials testified. Jencks declined to answer the question whether he was a member of the communist party. Government witness and FBI informer, Harvey Matusow, testified that he had met Clinton Jencks in 1950 at the San Cristobal Valley Ranch, near Taos, New Mexico, which they suspected was a meeting place for communists. Matusow testified that he discussed with Jencks what the Communist Party within the IUMMSW could do to hinder U.S. war efforts in Korea, and Jencks had identified himself to Matusow as a member of the Communist Party.

On April 17, 1953 only a few weeks after the movie crew had left, Jencks was arrested in Bayard for falsely filing a Taft-Hartley non-communist affidavit. His trial opened in the U.S. District Court, Western District of Texas, in El Paso on January 11, 1954. Judge R.E. Thomason, presided. Local 890 and the IUMMSW helped defend Jencks. Thirteen government witnesses claimed Jencks was a communist between 1946 and 1950 and Harvey Matusow testified again saying that Jencks had told him he was a communist after signing the Taft-Hartley affidavit. On January 22, 1954, the jury found Clinton Jencks guilty. He was sentenced to five years and was released on a $10,000 appeal bond.

The IUMMSW launched a Defense Committee to aid Clinton Jencks and appeal his conviction. However, before a hearing to request for a new trial could occur, Harvey Matusow admitted, in January 1955, to lying on the witness stand. Judge Thomason refused to grant a new trial for Clinton Jencks, but held Harvey Matusow in criminal contempt of court. The IUMMSW appealed again and the Jencks Case was en route to the U.S. Supreme Court in 1955.

During this time, the IUMMSW transferred Jencks from Bayard, New Mexico, to the International office in Denver in June 1953. Then he was transferred to the Tucson, Arizona, office in December 1954. From the Tucson office, Jencks worked with Locals #886 (Hayden), #915 (Ray), and #926 (Coronado). Then the International Executive Board of the IUMMSW requested Jencks to resign in January 1956. Jencks found himself unable to work for any company organized by the IUMMSW in the Southwest. In July 1956, he and his family moved to the San Francisco area. Though he worked for Stauffer Chemical and then as a machinist and maintenance millright, both jobs fired him after the FBI informed them he was a communist. On June 3, 1957, the U.S. Supreme Court reversed the lower court in the Jencks case voiding his conviction. Even after the Supreme Court decision, he had difficulties finding employment. The Justice Department finally dropped his case a year and half later.

In March 1959, Clinton Jencks was chosen for a Woodrow Wilson Fellowship to study economics, but the HUAC subpoenaed him to appear in Washington, D.C. in July 1959. The committee attempted to entrap Jencks into making statements in order to lay the basis for a second perjury charge. Jencks pled the Fifth Amendment. The Committee staff contacted the Woodrow Wilson National Foundation about the grant Jencks had received, noting that Jencks had taken the Fifth Amendment during his testimony. Unsure how this attempt to blackmail the Woodrow Wilson National Foundation would come out, Jencks returned to his job at the American Can Company. Two months later, he was notified that his one-year fellowship would be granted, and he enrolled in the University of California, Berkeley, for the fall semester, 1959.

In 1964, Clinton Jencks received a Ph.D. in economics from the University of California and became an Assistant Professor of Economics at San Diego State University in August 1964. Despite requests that his appointment be revoked because of his union work and allegations of communist connections, Jencks became a full professor in 1970. He retired in June 1986.

Jencks’ case was the first in a series of “conspiracy cases” against the IUMMSW. Clinton Jencks passed away December 15, 2005.


56.5 linear feet (160 Boxes)

Language of Materials



Clinton E. Jencks (1918-2005), joined the International Union of Mine, Mill, and Smelter Workers (IUMMSW) in 1946 while working at the Globe Smelter in Denver. In 1947 he became the IUMMSW local representative in the Silver City, New Mexico area. He led Local 890 in a strike against the Empire Zinc Mine in 1950 and the story of this strike is told in the 1953 film, Salt of the Earth. In 1954 Jencks ran afoul of the anti-communist hysteria when he was sentenced for perjury under the Taft-Hartley Act. After his conviction was overturned by the U.S. Supreme Court, Jencks pursued an academic career becoming a professor of economics at San Diego State University.


I. Personal

II. Constitutions of WFM & IUMMSW, 1893-1965

III. Local Unions & Ladies' Auxiliaries, 1892-1966

IV. Convention Proceedings of WFM & IUMMSW, 1900-1967

V. Executive Board Minutes of WFM & IUMMSW, 1902-1966

VI. Court Cases

VII. General Files, 1886-1993

VIII. Audio/Visual Materials

IX. Oversize

Immediate Source of Acquisition

Jencks began coordinating the acquisition and preservation of the IUMMSW’s records and also the records of its predecessor, the Western Federation of Miners (WFM). Through correspondence and field trips he located and secured documents, and also had records microfilmed. In 1967, Clinton Jencks gave the 1,095 linear feet of WFM/IUMMSW to the University of Colorado in addition to his own papers.

Processed by Harvey N. Gardiner, March 12, 2003
March 12, 2003
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Repository Details

Part of the University of Colorado Boulder Libraries, Rare and Distinctive Collections Repository

1720 Pleasant Street
184 UCB
Boulder Colorado 80503 United States