Major Twitter investor and ex-Microsoft CEO Steve Ballmer said social networks aren't currently able to prevent fake news.
But he does think they can help curb it.
With companies like Facebook, Twitter and Google facing heavy scrutiny from Congress over in the 2016 presidential election, Ballmer told Bloomberg TV on Monday that he'd like those companies to adopt a system that lets users know whether they're getting news from a trusted source.
He compared his plan to Twitter's blue-checkmark "verified" badge. Last week, Facebook introduced a feature offering context on articles posted on users' newsfeed. This includes a button that launches a pop-up window providing details about the article and its publisher.
Ballmer's comments come as Facebook disclosed last week that Russian-linked buyers had placed ads on the social network that were seen by 10 million people. Two weeks ago, Twitter said it had found more than 200 accounts on its platform connected to the buyers of the Facebook ads. And according to reports on Monday, a Google investigation found that Russian agents bought tens of thousands of dollars in advertising on YouTube, Gmail and Google search.
Twitter, Facebook and Google officials are expected to testify before Congress about Russian influence on their platforms on Nov. 1.
When asked about Twitter's ongoing harassment problems, Ballmer said while he believes in free speech, all social networks need to take action to remove "wholly inappropriate" content.
"There is a line once crossed, you need to make sure you are moving that stuff out of the public sphere," he said.
"It's what he's thinking," Ballmer said about Trump. "And every voter probably benefits from the ability to hear it directly."
This article originally appeared on CNET.