On Nov. 25, 1947, the head of the MPAA issued what has come to be known as the Waldorf Declaration, calling for an industry-wide ban of communists — and the organization still has not disavowed the statement.

In October 1947, the Cold War came to, or rather was declared on, Hollywood. For nine tumultuous days, the House Committee on Un-American Activities, chaired by a dapper martinet named J. Parnell Thomas (R-NJ), held its soon-to-be notorious hearings into alleged communist subversion in Hollywood. Officially dubbed "Hearings Regarding the Communist Infiltration of the Motion Picture Industry," it was the first full-on media-political spectacle of the postwar era. Like the kickoff for a successful franchise, it spawned like-minded sequels, but the first episode attracted the widest publicity and left the harshest legacy. Subsequent versions were low-energy imitations; the original was the high-profile template.

In all, 41 witnesses were called — studio executives, official representatives of the motion picture industry, producers, directors, screenwriters, actors, critics, investigators and lawyers. The first week was given over to witnesses mainly sympathetic to the committee, or at least not openly hostile, and were called "friendly," collectively "Friendlies." The recalcitrants — 19 in all — were dubbed "unfriendly" and embraced the tag as a badge of honor. They refused to answer what in those preinflationary times was called the $64 question: Are you now or have you ever been a member of the Communist Party? The Unfriendly Nineteen were whittled down during the hearings to the Unfriendly Ten, or the Hollywood Ten, although at the time Hollywood wanted no part of them.

The immediate blowback from the show trial was profound and long-lived. On Nov. 25, 1947, Eric A. Johnston, president of the Motion Picture Association of America, representing the executives of the major Hollywood studios, announced the peremptory firing of the Hollywood Ten. The studios pledged never again to employ a known Communist or unrepentant fellow traveler. At the studios and the networks, hundreds of artists were shown the door — or had it shut in their faces. Johnston’s declaration marked the formal onset of the blacklist era, a two-decade-long purgatory during which political allegiances, real or suspected, determined employment opportunities in the entertainment industry.

Johnston delivered his edict after a two-day meeting of some 50 top studio executives, producers and legal advisors at a closed-door conference at the Waldorf-Astoria Hotel in New York. The conclave was not just closed but unchronicled: No formal minutes were kept because no paper trail was wanted. MPAA bouncers blocked the entryway to the conference room, keeping pushy reporters at bay.

Film historians piecing together how the deal went down have had to rely on memoirs, legal documents and reports in the motion picture trade press. However, the best account comes from an inside-man who told his story to a government agency Americans in 1947 were unlikely to lie to: The FBI had an informant among the moguls. He may even have been a mogul, but his name remains redacted in the FBI files.

Among the powerbrokers in the room where it happened were Louis B. Mayer and Eddie Mannix from MGM; Jack and Harry Warner; Dore Schary from RKO; the two Cohns from Columbia Pictures, Harry and Jack; and independent producers Walter Wanger and Sam Goldwyn. The mogul of moguls, Nicholas M. Schenck, the president of Loew’s Inc., the parent company of MGM, lent his august presence, as did his brother Joseph Schenck, representing Fox, with Spyros Skouras, though the studio’s legendary production chief Darryl F. Zanuck, keeping his hands clean, was a no-show.

The MPAA's two big-name lawyers — behind-the-scenes consigliere James F. Byrnes and frontman Paul V. McNutt — were also on hand to advise on legal matters, assisted by two legal advisory committees — one from the studios, one from the New York offices — no fewer than seven additional lawyers.

The squadron of legal talent was on hand for good reason. The action the MPAA was contemplating placed the association and its member studios in serious legal jeopardy. Any coordinated action on the part of the producers might be read as a violation of the Sherman Anti-Trust Act — the very law, at that very moment, under which the Department of Justice was prosecuting the industry for monopolistic practices. If the producers acted together to dismiss the Hollywood Ten, they were conceding that the studios were in cahoots, conducting a conspiracy in restraint of trade. Moreover, the studios had entered into binding contracts with five of the accused screenwriters. Studio writers could be fired for incompetence, disobedience or moral turpitude, but not for refusing to answer questions before Congress.

For two days, the moguls and the lawyers debated the legally treacherous and culturally sensitive terrain. The group had two options: to continue to employ the Hollywood Ten and risk the further alienation of the American public — or flat-out fire the liabilities.

Johnston took charge of the proceedings and moderated throughout. Just two years before, the globally minded businessman and former head of the U.S. Chamber of Commerce had been appointed to replace Will H. Hays, the head of the MPAA since its founding in 1922. Still in Hays’ shadow, Johnston had no desire to see his tenure dominated by endless wrangling with HUAC and anticommunist pressure groups. Schary recalled that Johnston spoke to the assembly "as if we were members of an industry manufacturing secret deadly weapons by employing communists." Johnston argued that if Hollywood refused to blacklist the communists, moviegoers would blacklist Hollywood.

By all accounts, a raucous debate ensued. Three liberals (Goldwyn, Schary and Wanger) and one ornery cuss (MGM plant manager Mannix) opposed the emerging consensus to fire the Ten. A subcommittee chaired by Nicholas Schenck was appointed to meet after-hours and hammer out an agreement.

The proposal was shared with the full group the next day. According to the FBI informant, during a recess on that contentious second day, Goldwyn told Johnston that he planned to hire some of the communists who were fired and thus "pick up some good talent" on the cheap "and then watch them closely for possible propaganda."

When the meeting resumed, Johnston "asked permission to address the group," reported the FBI's mole, "and gave a brilliant and bitter speech."

The usually mild-mannered businessman was furious that the producers refused to commit to decisive remedial action. "Gentleman, I don't know why you hired me," he said. "I don't need this job. You won't listen to me. You won't take my advice, you don't mean what you say and you have no guts."

Goldwyn stood up. "Eric, I feel you are talking to me," he said, preparing to respond.

At that point, Joe Schenck cut Goldwyn off. "Don’t make a speech, Sam," he snapped. "Sit down and shut up or get out."

Goldwyn sat down and the meeting proceeded. "Informant pointed out this incident as one which helped to clarify the air in the New York sessions" was the dry comment from the FBI handler.

At 2 p.m., in a tense moment of truth for all, the assembly faced the "fish or cut bait" moment as Johnston called it. The statement was put to a standing vote. Every man rose to affirm his assent.

Thirty minutes later, in time to make the late-afternoon editions of the metropolitan dailies, MPAA publicity man Tom Waller emerged from the room and handed out mimeographed copies of the statement to newsmen and photographers jamming the corridor. Johnston did not make an appearance to answer questions, but he filmed a newsreel segment to explain the policy to moviegoers.

What quickly became known as the Waldorf Declaration was a mixture of mealy mouthed duplicity and steely eyed calculation. "We do not desire to prejudge their legal rights," Johnston said of the Hollywood Ten, "but their actions have been a disservice to their employers and have impaired their usefulness to the industry."

Then, the coup de grace:

"We will forthwith discharge or suspend without compensation those in our employ and we will not reemploy any of the 10 until such time as he is acquitted or has purged himself of contempt and declares under oath that he is not a Communist."

However, the vigilance would not cease with the termination of the Ten:

"We will not knowingly employ a Communist or member of any party or group which advocates the overthrow of the government of the United States by force or by any illegal or unconstitutional methods."

Johnston conceded that the policy "involves dangers and risks" and that it had the potential to hurt "innocent persons," but the present emergency demanded stern measures.

Having weighed the legal expenses against the box-office grosses, Johnston and the moguls opted to take a calculated risk. Lawsuits from the fired men under contract would inevitably follow, but the court judgments against the studios would be less costly than the verdict of moviegoers at the box-office window. "We'll fire them and let 'em sue" was the response from a top executive quoted in The Hollywood Reporter.

The Waldorf Declaration remained official industry policy throughout the coldest years of the Cold War. As the 1950s wore on, however, cracks in its enforcement opened up. With increasing brazenness, the studios employed "fronts" and accepted pseudonymous contributions from nominally blacklisted screenwriters. By the time Dalton Trumbo, a member of the original Hollywood Ten, received an Oscar for best original screenplay for The Brave One (1956), under the handle Robert Rich, his covert authorship was an open secret around town. In 1959, Trumbo went on television and spilled the beans to a national audience. The next year, first Otto Preminger and then Kirk Douglas each said they would hire Trumbo for Exodus and Spartacus, respectively.

Responding to accusations by the American Legion that Hollywood was "surreptitiously employing known Communists," Johnston restated the MPAA's support for the Waldorf Declaration. "The policy of the Motion Picture Association is not to employ known Communists," he insisted in 1961. The policy has not changed."

But the game was up. By then, there was nothing surreptitious about the employment of known Communists. The enabling document of the Hollywood blacklist was shredded the moment Trumbo saw his name unspool during the opening credits to Spartacus, which had its gala premiere on Oct. 19, 1960, at the Pantages Theater in Hollywood.

Yet while allowed to lapse, the Waldorf Declaration was never officially disavowed by the MPAA. I recently asked the association if it had ever voted to repudiate or apologize for the Waldorf Declaration. "Unfortunately, at this time the information you are seeking is not available to the public" was the response in an email. "A vote, such as the one you are inquiring about, would be recorded in meeting minutes of the MPAA's Board of Directors and/or Members and as such, such information is confidential and solely intended for the MPAA Board and its Members."

In 1947, the MPAA heralded the Waldorf Declaration far and wide, in the press and on the newsreel screen. Seventy years later, the MPAA refuses to issue a simple declarative sentence.

Thomas Doherty is a professor of American Studies at Brandeis University and the author of Show Trial: Hollywood, HUAC, and the Birth of the Blacklist, which is set to be published by Columbia University in March 2018.