A regulator whose vote could be needed to advance President Donald Trump’s order to reduce legal protections for Twitter Inc. and other social media companies has expressed doubt about the change.

Michael O’Rielly, a Republican member of the Federal Communications Commission that’s slated to write the social-media rules, said he wasn’t sure the agency has power to grant Trump’s request. Republicans hold a 3-2 edge at the FCC.

“Did Congress provide us authority to act?” O’Reilly said in an interview for the C-Span television show “The Communicators.” O’Rielly said he hadn’t taken a position on the merits of the issue, which he said also involved questions of First Amendment free-speech protections.

Trump on May 28 signed an executive order to reduce liability shields for social media after Twitter began selective fact checks of his posts on the platform. The order directs the U.S. Commerce Department to ask the FCC to being a rulemaking this summer.

FCC Chairman Ajit Pai, a Republican, has said the agency will review the proposal. The third Republican commissioner, Brendan Carr, called Trump’s executive order “really welcome news” on the day it was signed, and said he looks forward to acting on the administration’s request.

The idea met a cool reception from the agency’s two Democrats, including Commissioner Jessica Rosenworcel who said that to “turn the Federal Communications Commission into the President’s speech police is not the answer.”