The Department of Justice (DoJ) has refused to explain why a meeting with an anti-gay group undertaken by Attorney General Jeff Sessions was held behind closed doors.
Sessions, a key ally of US President Donald Trump, met members of the Alliance Defending Freedom (ADF) at a closed event in Orange County, California, supposedly to discuss religious liberty.
The news was first broken by Buzzfeed journalist Dominic Holden, who said on Twitter the DoJ declined to comment on the meeting.
The ADF is involved in a landmark Supreme Court case on same-sex marriage, centring on a Christian baker in Colorado, Jack Phillips, who refused to bake a wedding cake for a gay couple. The group has backed Phillips in his case.
The Southern Poverty Law Center, a prominent anti-extremism group, has branded the ADF a hate group, but it disputes this description.
Same-sex marriage was legalised across the United States under the Obama administration, but Holden speculated there may a change in the DoJ's position on gay marriage given Sessions' decision to attend the ADF meeting.
The Democratic National Committee condemned Sessions' decision to attend in an official statement.