The conference started about 11 a.m. Sunday and was scheduled to continue until 8 p.m. Caterers at Rocklands Farm served brunch, and participants recapped 2017. At about 4 p.m., Spencer said, someone working the event learned that Spencer was there, and management told everyone to leave.
"We didn't lie, we didn't deceive, and we certainly did not break any rules while we were there," Spencer said. "We had sharp words and were obviously disappointed, but there was no confrontation of any kind."
The farm refunded the group's money after asking it to leave.
The owners of Rocklands Farm didn't comment on the incident beyond a statement on their website Monday, which says it proudly does "business according to family values, including welcoming people of all backgrounds, race, ethnicities, cultures, and religions."
The statement continued: "Throughout our history of hosting private events, we have never had to ask a group to leave. However, yesterday, November 19, we discovered that a private event held here was, in reality, a gathering of an organization that is strongly in opposition to our values. We immediately and politely asked the group to leave. We are grateful that the group agreed to peacefully leave."
The National Policy Institute booked space at Rocklands Farm after the property manager at the Ronald Reagan Building and International Trade Center, a federal facility in the District, told the organization that it couldn't host its conference at the building. The two sides had been in communication for months before a private management company rejected the request over safety concerns.
Spencer's public appearances have been a lightning rod in recent months, both for the content of his speeches and questions over free speech. His events often attract large numbers of protesters.
The University of Florida reluctantly agreed last month to allow Spencer to speak on campus after initially rejecting his request. Spencer and his lawyer challenged the initial decision, citing First Amendment concerns. The university paid hundreds of thousands of dollars for security at the event.
Spencer described the Rocklands Farm gathering as a policy conference, in which attendees paid $225. Spencer said before the event that it was to feature Daniel Friberg, the European editor of AltRight.com, and Kevin MacDonald, described by the Southern Poverty Law Center as "the neo-Nazi movement's favorite academic."
The organizers didn't publicly disclose beforehand that the event would be held at Rocklands Farm, Spencer said. Instead, organizers arranged for vans to pick up attendees at various locations and drive them to the farm.
After Rocklands Farm management told them to leave, those vans then shuttled the conference attendees to another private space outside the District before they then went to dinner at a restaurant, Spencer said.
"I'm not mad, but if I were a business owner, I would not do that," Spencer said. "If communists came to my establishment, but they were civilized, I couldn't imagine kicking them out. So I'm certainly disappointed, but we are not going to retaliate. It's just life in 2017 for us."
Spencer was one of the leaders of a white-nationalist rally in Charlottesville in August. The march at the University of Virginia — with participants chanting "Jews will not replace us!" — touched off violence between demonstrators and counterprotesters that turned deadly the next day when a man drove into a crowd, killing one woman and injuring others. Two police officers who were monitoring the protests died when their helicopter crashed.