The election-interference indictment brought by Robert Mueller, the U.S. special counsel, underscores how thoroughly social-media companies like Facebook and Twitter were played by Russian propagandists. And it’s not clear if the companies have taken sufficient action to prevent something similar from happening again.

Thirteen Russians, including a businessman close to Vladimir Putin, were charged Friday in a plot to interfere in the 2016 U.S. presidential election through social media propaganda. The indictment said the Russians’ conspiracy aimed, in part, to help Republican Donald Trump and harm the prospects of his Democratic opponent, Hillary Clinton. 

The alleged scheme was run by the Internet Research Agency, a troll farm based in St. Petersburg, Russia, which used bogus social media postings and advertisements fraudulently purchased in the name of Americans to try to influence the White House race.  

“It’s backed by the Kremlin, and there are ties to (Vladimir) Putin there,” CBS News’ Jeff Pegues said Friday. “So what investigators are alleging in this indictment is that through this Internet Research Agency, the organization was able to influence events here in the U.S. by using social media to, for example, set up fake protests, in some cases, for and against Trump. Or against other candidates in the 2016 election.”  

One of the defendants, Irina Kaverzina, wrote in an email to a family member obtained by investigators, “I created all these pictures and posts, and the Americans believed that it was written by their people.”

Deputy Attorney General Rod Rosenstein said the indictment is a reminder that “people are not always who they appear to be.”

Tech companies have spent months pledging to fix their platforms ahead of the upcoming midterm elections this year, and reiterated those promises Friday. In a statement, Twitter said it is “committed to addressing, mitigating, and ultimately preventing any future attempts to interfere in elections and the democratic process, and to doing so in the most transparent way possible.” 

“Russian efforts to disrupt the 2016 U.S. election, in part by abusing social media platforms, go against everything we at Twitter believe,” the statement said. “Any activity of this kind is intolerable, and we all must do more to prevent it.”

Facebook thanked U.S. investigators for taking “aggressive action” and pointed out its own role in helping the investigation. 

“We know we have more to do to prevent against future attacks,” said Joel Kaplan, vice president of global policy at Facebook, in a statement. “We’re making significant investments, including increasing the number of people working on security from 10,000 to 20,000 this year.” 

“As we said publicly last year, this kind of foreign interference violates all of our values,” he said. “These indictments now say it also violated the law.”

Researchers, however, noted that the companies’ business incentives don’t necessarily align with improved security and anti-hoaxing measures that might have frustrated Russian agents.

“I’ve never been convinced that these sites are motivated to fix a problem like this,” said Notre Dame business professor Timothy Carone, who added that security controls make it harder for sites like Facebook to offer users new features and keep advertisers happy. “It’s a really, really, really difficult problem.”

The indictment confirms earlier findings from congressional investigations that Russian agents manipulated social media to promote social division by mimicking grassroots political activity. It also underscores that the problem wasn’t just “bots” — i.e., automated social-media accounts — but human conspirators who fine-tuned propaganda and built online relationships with American activists. 

“The idea wasn’t necessarily to help one political party over another, but to sow as much discord as possible,” said Melissa Ryan, a Democratic social media marketing expert who now keeps track of right-wing online activity. “This was America that was attacked.”

Social-media companies weren’t the only ones subverted in the influence campaign. Federal prosecutors allege that Russian criminals used PayPal as a primary conduit to transfer money for general expenses and to buy Facebook ads aimed at influencing voters. Prosecutors say the accounts were opened using fake identities to help bypass PayPal’s security measures.

PayPal spokesman Justin Higgs said the San Jose, California, company has been cooperating with the Justice Department and is “intensely focused on combatting and preventing the illicit use” of its services.

In an interview with The Associated Press on Tuesday, Facebook Chief Technology Officer Mike Schroepfer outlined the complexity of preventing abuse.

“Election integrity is challenging because again, you’re dealing with adversaries,” Schroepfer said during a conference in Half Moon Bay, California. “They are trying to accomplish a goal and they have smart people who are trying to figure out their way into the system to accomplish that.”

For instance, infiltrators often react immediately to countermeasures. If they figure out Facebook is checking the internet addresses of computers to identify visitors from particular countries, Schroepfer said, “they’ll take over a machine with malware in the U.S. and post from there instead. People say, ‘Why don’t you just check the currency or the IP address?’ And as soon as you do that, literally that afternoon, they will change tactics.”

Schroepfer said the company is making “good headway” on the problem, although he declined to give specifics. “By kind of doing a lot better job of trying to figure out the authenticity of these different actors, we can certainly stop that sort of behavior,” he said. “There’s a big focus on that.”

On the other hand, now that the Russians have shown how this sort of campaign is done, the door is open for others — including American special interest groups — to use the same tactics to target disaffected voters in the right places, said David Gerzof Richard, a communications professor at Emerson College.

“This is the new norm,” he said. “It’s not going away. It’s not going to be magically fixed by a Silicon Valley CEO or a group of executives saying they’re going to do better.”

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