A new idiom entered the lexicon of the tussle between Republicans in Congress and the social media platforms they believe suppress conservative voices: the “censorship-industrial complex.”

First used by journalist Matt Taibbi and author Michael Shellenberger Thursday morning in another chapter of what has come to be known as the “Twitter files,” the phrase describes the growing practice of government actors collaborating with think tanks, non-governmental organizations, and media watchdogs to pressure social media companies such as Twitter and Facebook to tamp down content labeled as “misinformation” — even if the information is factually accurate — and divert advertising dollars away from conservative-leaning news sites.

The practice was laid bare during the second hearing of the Republican-led House Judiciary Committee’s new select subcommittee on the weaponization of the federal government, at which Messrs. Taibbi and Shellenberger testified Thursday. The censorship documented by the two men began as an attempt ostensibly aimed at combating online extremism by terrorists or Russians meddling in American elections, but has evolved into a fight against what its players describe as “domestic misinformation,” Mr. Shellenberger said.

“It’s not a slippery slope,” he told the committee. “It’s an immediate leap into a terrifying mechanism that we only see in totalitarian societies.”

Mr. Taibbi went a step further, describing the links between government agencies and their private-sector proxies — and the censorship they encouraged — as a form of “digital McCarthyism.”

“We learned Twitter, Facebook, Google, and other companies developed a formal system for taking in moderation ‘requests’ from every corner of government,” Mr. Taibbi said. “For every government agency scanning Twitter, there were perhaps 20 quasi-private entities doing the same, including Stanford’s Election Integrity Project, Newsguard, the Global Disinformation Index, and others, many taxpayer-funded.

“A focus of this fast-growing network is making lists of people whose opinions, beliefs, associations, or sympathies are deemed ‘misinformation,’ ‘disinformation,’ or ‘malinformation,’” he added. “The latter term is just a euphemism for ‘true but inconvenient.’”

Representative Mike Johnson, a Louisiana congressman on the committee, said the details unearthed in the Twitter files to date suggest that “Twitter was basically an FBI subsidiary before Elon Musk took over.

“The Twitter files should be a matter of bipartisan concern for every member of Congress and every American citizen, because it is a bedrock principle of our system that the government does not get to decide what speech is acceptable or true,” Mr. Johnson said.

Democrats on the committee expressed skepticism about what they said were “right-wing conspiracy theories” and suggested that, if the shoe were on the other foot, Republicans would be raising cain. 

“I’m pretty sure that if the Democrats held a hearing today to force Fox News to post certain content, my Republican colleagues would be up at arms,” Representative John Garamendi, a California Democrat, said. “This is particularly ironic because we know for a fact that Fox News does spread disinformation, and does so while knowing that the material is false.

“No private company has an obligation to amplify anything, and especially not messages that strike at the heart of our democracy,” Mr. Garamendi said.

The latest installment in the Twitter files shows that content moderators at Twitter regularly exchanged spreadsheets with the names or accounts of thousands of users whose posts or comments were deemed problematic. Many were indeed malicious actors spreading false or misleading information about elections or propaganda on behalf of malign foreign players such as Iran or Russia. Many others, though, were not. Among those caught up in these nets were a reporter for the Chicago Sun Times and an Iraqi war veteran who blogged about the war, according to the report.

Among the information flagged for removal or censorship were  “anti-Ukraine narratives” and posts that were technically true but that promoted “vaccine hesitancy,” according to the report. Moderators should watch closely for “viral posts of individuals expressing vaccine hesitancy, or stories of true vaccine side effects,” the censors were informed.

“This content is clearly not mis or disinformation, but it may be malinformation (exaggerated or misleading),” one watchdog reported. “Also included in this bucket are often true posts which could fuel vaccine hesitancy, such as individual countries banning certain vaccines.”

Twitter’s reliance on a network of private actors in the disinformation policing space was even greater than its cooperation with government agencies, Mr. Taibbi and his colleague reported. Non-governmental players with lofty names like the Alliance Securing Democracy, the National Endowment for Democracy, and the Aspen Institute played pivotal roles in the campaign to suppress speech, the report said.

The Aspen Institute, which receives millions of dollars in funding annually from the American taxpayers and is described as the “Woodstock of the Censorship-Industrial Complex” by Mr. Taibbi, released a report in August 2021 stating that governments should have complete access to data held by social media platforms in order to better police online speech and restrict disinformation, “even if it means losing some freedom.” Among its other recommendations were that governments should empower agencies like the Federal Trade Commission to police social media platforms “in the public interest.”

The role of the FTC became a major flashpoint during Thursday’s hearing because the committee reported earlier that within weeks of the first of the Twitter files coming online, the agency began demanding information from Twitter about the changes Mr. Musk was making to the platform after he purchased it in October 2022. Twitter has been under a consent decree with the agency for improperly safeguarding user data long before Mr. Musk bought the company.

Among the information requested by the agency were the names of those who had written about the Twitter files, including Messrs. Taibbi and Shellenberger. Mr. Taibbi said the FTC’s demands should send shivers down the spines of journalists everywhere.

“I think it’s none of the government’s business which journalists a private company talks to and why,” Mr. Taibbi said. “I think every journalist should be concerned about that, and the absence of interest in that issue by my fellow colleagues in the mainstream media is an indication of how low the business has sunk.”

The Democrats on the committee attempted to discredit the writers, both of whom described their politics as liberal-leaning — Mr. Shellenberger said he voted for President Biden — as being “hand-picked” by Mr. Musk and using “cherry-picked” data to support their narrative about an assault on free speech and the First Amendment.

“It may be possible — if we can take off the tin foil hat — that there is not a vast conspiracy, but that ordinary folks and national security folks responsible for our safety are trying their best to find a way to make sure that our online discourse doesn’t get people hurt or our democracy undermined,” Congressman Colin Allred of Texas said. “The very rights you think they undermine, they are trying to protect.”