Brendan Smialowski / AFP/Getty Images

Hindsight is 2016.

Facebook, Google and Twitter representatives, testifying at a Senate committee hearing on Wednesday, said they learned important lessons from how fake news and Russian propaganda spread across their sites during the 2016 US presidential election. And they're working to make sure it doesn't happen again in 2018.

The three companies laid out plans that promise more transparency and proactive measures to prevent propaganda.

Experts say the 2018 midterm election has the potential to shift the political landscape ahead of the next presidential election. That just bolsters lawmakers' interest in getting answers from the tech giants, whose platforms are lead disseminators of election information, on how they're going to prevent a repeat of 2016. Senators grilled the same three companies last November after they failed to stop the Russian misinformation campaign in 2016.

Carlos Monje, Twitter's director of public policy and philanthropy, said the company created a "cross-functional elections task force" for the midterms with plans to:

Verify party candidates to prevent copycat accounts



Work with federal and state election officials to manage any issues



Improve its algorithm to stamp out bot accounts targeting election-related content



Monitor trending topics and conversations related to the 2018 election for any fake news



Use its Ads Transparency Center for political ads



Monje also told the committee that Twitter is working to inform users who had been exposed to Russian propaganda in 2016, similar to what Facebook did last November.

Sen. Mark Warner, the top Democrat on the Senate Intelligence Committee who has been grilling tech companies like Twitter for more transparency, tweeted his support.

After months of pushing Twitter to do the right thing, I’m encouraged the company will soon notify users who saw content from Kremlin-backed trolls. https://t.co/aefyqbn0FC — Mark Warner (@MarkWarner) January 17, 2018

Meanwhile, Juniper Downs, YouTube's head of public policy and government relations, described Google's actions as a four-step plan:

Require advertisers to identify who they are and where they're from



Provide disclosures on political ads telling viewers who paid for them



Release a transparency report on election ads



Publish a "creative library" where all the purchased ads are made public



Facebook said it would be increasing its political ads transparency and highlighted the tools it added to fight fake news, such as machine learning and adding a "Related Articles" section in articles for context.

The hearing took place as Facebook announced in a letter to the UK Parliament that it's reopening its investigation into Russian interference with Brexit.

"Political ads are a little bit more complicated, but certainly an area where we think increased transparency is important," Monika Bickert, Facebook's head of global policy management, said at the hearing.

Clinton Watts, a Foreign Policy Research Institute fellow, criticized the companies during the hearing, stating that what they're doing would not be enough, as propaganda always tends to stay one step ahead of the website's watchful eye.

"They understand the terms of services, they have the capabilities to actually beat those systems. They play within the rules," Watts said.

First published Jan. 17 at 11:51 a.m. PT.

Update at 3:53 p.m. PT: Adds comments from Twitter exec and reaction from Sen. Mark Warner.

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