Facebook has brought in a high-profile Washington insider to advise the company on concerns over whether its employees and content-filtering algorithms have an anti-conservative tilt.

Former Arizona GOP Sen. Jon Kyl — now with Capitol Hill lobbying stalwart Covington and Burling — is partnering with the tech giant as lawmakers hammer it for a lack of transparency, not doing enough to combat fake news ahead of the 2016 election, and — if you ask many Republicans — having a built-in bias in its codes and personnel that shuts out conservative voices.

Facebook is also working with civil rights leader Laura Murphy, who will lead a legal audit of the company’s impact on minority communities.

The partnerships, first reported by Axios, come a week after lawmakers traded verbal blows on the issue in a House Judiciary Committee hearing where one Democrat called the notion of Facebook’s anti-conservative bias a “hoax” meant to shore up political support from misinformed voters.

GOP Rep. Marsha Blackburn of Tennessee and others disagree.

“Big Tech platforms are the new public square, and their executives, as the gatekeepers, are the new governors,” Blackburn told the committee last week. “But these governments do not have a First Amendment.”

Blackburn is the former communications chairwoman of the Republican Study Committee and currently chairs the Energy and Commerce Subcommittee on Communications and the Internet, where she has led a broad campaign to dismantle net neutrality regulations.

Experts have told Congress that the case against Facebook for having anti-conservative bias is tenuous.

Ari Waldman, a professor at New York Law School, told the committee last week that much of the criticism of Facebook’s filtering algorithms stems from when the company redesigned its news feed algorithm to emphasize content from users’ friends and families instead of news sites.

“The result is that lots of content gets filtered out, but no more so from the right than from the left.”

Facebook steered its news feed in that direction after critics excoriated it for not doing enough to prevent false and biased news stories from proliferating on its platforms leading up to the 2016 elections.

Now, certain keywords and images sometimes trigger suspensions on people’s posts and accounts — regardless of their context.

Victims of racism, homophobia, and sexism on Facebook who post about their experiences often have their content removed or are suspended or banned for containing those key words. The company’s computers have removed pictures of breastfeeding mothers. An artist who has posted portraits of gay soldiers on his Facebook account has been blocked.

“At a minimum,” Waldman said, “mistakes happen on the left just as much as they happen on the right.”

Watch: Diamond and Silk Tell Congress ‘Facebook Censored Our Free Speech’