What Did Cambridge Analytica Really Do for Trump's Campaign?

News that Cambridge Analytica CEO Alexander Nix approached Wikileaks founder Julian Assange last year to exploit Hillary Clinton’s private emails has amplified questions about Cambridge's role in President Trump's 2016 campaign.

Shortly after The Daily Beast reported Nix’s contact with Assange Wednesday, the Trump campaign’s executive director sought to downplay Cambridge's role. Michael Glassner said in a statement that the Republican National Committee was the campaign’s primary source of voter data. “Any claims that voter data from any other source played a key role in the victory are false,” Michael Glassner wrote. The statement did not respond to reporting in WIRED and elsewhere revealing a close relationship between the Trump campaign and Cambridge staffers. Cambridge did not respond to WIRED's request for comment.

So, what gives? Such he-said-she-said battles are usually better left to Beltway happy hours. But as Congress and special investigator Robert Mueller turn their spotlights on Cambridge Analytica in their probes into Russian meddling in the 2016 election, it’s essential to get the facts straight about what the firm did—and didn’t—do for the Trump campaign.

Here’s what we know.