The election was a chance for Facebook and Twitter to show they could control misinformation. Now lawmakers are grilling them on it.

WASHINGTON - Twitter and Facebook executives fielded familiar questions from lawmakers on Tuesday about their moderation and labeling practices, but they barely scratched the surface on the efficacy of their efforts during the 2020 election.

Both social media companies took unprecedented steps to limit the spread of election misinformation both before and in the weeks following the election. Eventually lawmakers asked about those interventions, but not before focusing on individual lawmaker's pet issues with the executives, including unsubstantiated claims of bias against conservatives and concerns the companies have become too dominant in the market.

Twitter's Jack Dorsey and Facebook's Mark Zuckerberg had last been before a Senate committee just three weeks ago, when they appeared before the Senate Commerce Committee to answer questions about their companies' content moderation practices.

Republican members of the Senate Judiciary Committee on Tuesday were quick to condemn the sites for labeling President Donald Trump's false claims that he won the election, and said it was time to rein in their power.

"You have used this power to run amok, you have used this power to silence conservatives," said Sen. Marsha Blackburn, R-Tenn.

But Democrats also asked questions about the sites' use of labels to warn users that a post might be disputed or inaccurate.

Sen. Dianne Feinstein, D-Calif., asked if Twitter's labels on Trump's posts that noted official sources might have called the election differently were effective enough. Dorsey said they were sufficient, along with the link Twitter provided for users to get more information.

"I do believe that connecting people to the larger conversation, to give them more context, is the right avenue," Dorsey said.

The hearing highlighted the partisan divisions over Silicon Valley's recent crackdown on misinformation that have been evident throughout the election campaign, with Republicans accusing the companies of going too far in labeling or otherwise limiting the spread of falsehoods, and Democrats demanding they do more, especially as Trump and his allies continue to use Twitter and Facebook to spread claims of election fraud without evidence.

The most noticeable change in the hearing wasn't about content, but appearances. Dorsey, for example, had trimmed his widely-discussed beard since his last testimony and appeared to be testifying from a kitchen in front of stacks of dishes on open shelves.

Tuesday's showdown also was more disorganized and lacking in a clear focus than previous tech hearings. Senators from both parties frequently exceeded the seven-minute time limit they'd been given for questioning, and they jumped from election misinformation to antitrust to tech addiction.

The hearing crystallized long-running criticisms that Washington lawmakers are ill-equipped to take on large tech companies. Lawmakers circled around important issues about how the tech companies handled misinformation during the election. But they repeatedly failed to gain new information about whether the many new interventions tech companies applied during the 2020 election had been effective in stopping the spread of falsehoods and other inflammatory content.

Lawmakers from both parties gave blistering assessments of the companies and said greater regulation of Silicon Valley was needed, signaling that could be a greater priority in the next Congress."The bottom line is we want to make these platforms better," Committee Chairman Lindsey Graham, R-S.C., said. "We want to continue to grow this part of our society responsibly, and right now without regulation or lawsuit, it's becoming the Wild Wild West."

But the lawmakers' competing assessments of the tech companies' moderation efforts during the just-ended campaign reflected the country's political polarization that makes it unclear how Congress might overcome its differences to pass meaningful regulation of the tech companies.

"I think there's one certainty here and that's that Mr. Dorsey and Mr. Zuckerberg will be back in the next Congress," said Sen. Richard Blumenthal, D-Conn. He also called for the executives of Facebook and Amazon to testify as well. (Amazon chief executive Jeff Bezos owns The Washington Post).

Graham kicked off the hearing by calling for changes to Section 230, the law that protects Internet companies from much liability for what their users post online and that faces bipartisan criticism. Graham and Blumenthal have introduced bipartisan legislation to revise Section 230, called the EARN IT Act.

"When you have companies that have the power of governments, have far more power than traditional media outlets, something has to give," Graham said.

Dorsey said that the company had overhauled its policies in light of the backlash that greeted its decision to block the sharing of New York Post articles involving alleged emails about Hunter Biden that were reportedly found on an abandoned laptop. Dorsey admitted the company had made a mistake when it assumed the articles violated its policies on hacked materials, and he noted that the company had admitted the error within 24 hours, notified the New York Post and changed the policy.

"I hope this illustrates the rationale behind our actions, and demonstrates our ability to take feedback amid the stakes and make changes all transparently to the public," Dorsey said.

Dorsey called on lawmakers to work with tech companies to build on Section 230, and warned against changes that could limit competition. Dorsey reiterated the company's commitment to addressing attempts to undermine voting. He pointed out that Twitter labeled about 300,000 tweets in the lead-up to the election and the week following on content that was potentially misleading.

Zuckerberg focused on Facebook's efforts to combat misinformation and voter suppression. Zuckerberg said the company removed false claims about polling conditions in coordination with local law enforcement and partnered with third-party fact-checkers to suss out misinformation. He also acknowledged that the company's work on election interference is not done.

"We try to do what's best for our community and the world, acknowledging that there are difficult trade-offs," Zuckerberg said. "I believe that some of these trade-offs would be better made through a democratic process."

In one of the most substantive exchanges of the hearing, Zuckerberg recommended that any new regulations should require companies to issue transparency reports about the results and efficacy of their content moderation systems.

"That way, the people who are responsible for holding all of us accountable - whether it's journalists, Congress, academics - could have an apples to apples comparison of how all the other companies are doing, and potentially as part of a law, require companies maintain a certain level of effectiveness," Zuckerberg said.

Social media companies already make transparency reports available, but they often categorize or report their takedowns differently, making it difficult to compare from business to business.

Tech chief executives have become a common fixture on Capitol Hill as the political backlash against social media companies has swelled in recent years. Zuckerberg avoided testifying in front of Congress at all for the first 14 years of Facebook's existence, but this will be his third virtual appearance since July.

Dorsey has been a far less frequent witness, but his company faces greater ire from Republicans. The company has taken aggressive steps in recent weeks to limit posts from Trump that make false or unsubstantiated claims about the election.

Twitter has said its labeling accounted for about 0.2 percent of all election-related content. But researchers say there still is not enough data available to determine how effective the interventions were.

Tuesday's hearing was scheduled last month after Republicans on the committee voted to subpoena Dorsey and Zuckerberg in response to the steps they took to limit the spread of the New York Post articles, though they ultimately agreed to appear in front of the panel voluntarily.

Graham said in a statement that the hearing would focus on the "censorship and suppression" of the articles and that it would also provide lawmakers "a valuable opportunity to review the companies' handling of the 2020 election."

Democrats focused on Trump's use of social media to spread baseless claims about mail-in ballots and voting machines. Blumenthal accused the companies of giving the president a megaphone to spread falsehoods "in an apparent attempt to overturn the will of the voters." He said the companies' efforts are only "baby steps" and called on them to take greater responsibility for their services.

Blumenthal noted that no executive from Google, which owns YouTube, was called to testify at today's hearing. He criticized Google for being less aggressive about misinformation than Facebook and Twitter. He also said he hopes that the committee could have a series of hearings on tech issues in the future, addressing issues including antitrust and Section 230.

Blumenthal also called the Republicans' focus on censorship a "political sideshow."

"This hearing is a betrayal of the real victims of the real harms caused by Big Tech," he told Dorsey and Zuckerberg. "You have repeatedly and catastrophically failed the American public."

Sen. Patrick J. Leahy, D-Vt., turned the hearing back to the election, asking both CEOs if they had conducted a post-mortem of their response to misinformation. Dorsey and Zuckerberg both said they have a plan to do so and that they will allow some academics to have access to their companies' information to do independent analyses.

"We have taken action on tweets from leaders all around the world, including the president," Dorsey said in response to Republican questioning about fact-check labels.

The Biden campaign has had a publicly contentious relationship with Facebook and repeatedly accused the company of not going far enough to prevent the spread of election-related misinformation. Democrats are also pushing for more-aggressive antitrust enforcement against the tech industry, and the Federal Trade Commission is expected to file an antitrust lawsuit against Facebook as early as this month.

The repeated hearings have given lawmakers a platform to air their grievances with Silicon Valley, but so far no meaningful regulation has resulted from them.