It was a perfectly beautiful summer night on the Boston waterfront, and a group from the Conservation Law Foundation and some of their supporters walked along the public path known as the Harborwalk. But as the group walked up to the Institute of Contemporary Art, they found their path blocked by a metal barrier.

On the other side, hundreds of people, mostly in dressy all-white outfits, chatted and sipped cocktails. 

“Can we go in here?” Deanna Moran of CLF asked a security guard stationed there.

“No," he said. "You have to go inside and talk to one of the one of the staff members in there.”

“OK. So the Harborwalk is closed right now?” Moran asked. The security guard looked a little flummoxed and grabbed his radio, asking for someone to come to the gate.

Deanna Moran and others from the Conservation Law Foundation speak with a security guard at the ICA.
Meredith Nierman/WGBH

The ICA was the last stop on a sort of travelling picnic along the waterfront the CLF group did on this evening to illustrate a point – that these spots, even though it might not always seem like it -- especially those in front of swanky hotels and luxury condos -- are open to the public, by state law.

CLF employees and supporters dropped picnic blankets at spots along the Harborwalk.
Meredith Nierman/WGBH

After a while, ICA Director of Events Hannah Gathman greeted the CLF group. Gathman explained that this was the museum’s monthly summer "First Fridays" event. The ICA does host a number of events in the public space here that are free and open to the public. But this one cost $20 for non-members.

The property on the other side of the ICA is under construction, interrupting the continuous Harborwalk, and Gathman said that’s why the public path around the museum is shut down.

“Then why can people access the Harborwalk during the day when you're not having an event?” Moran asked.

“I don't know," Gathman replied. "I'm sorry I don't have a better answer for that.”

ICA Director of Events Hannah Gathman speaks with people from CLF.
Meredith Nierman/WGBH

Moran asked if the ICA had prior authorization from the state's Department of Environmental Protection, which is responsible for the Harborwalk, to have a private event there. Gathman said she didn't know.

The answer is no. The DEP did not give the ICA permission to shut the Harborwalk down.

“It's an example of encroaching privatization we're seeing, where what's public by law is becoming private in practice,” said Brad Campbell, president of the Conservation Law Foundation. Campbell called their picnic event on public spaces an "act of civil obedience."

“Whether it's for a private event or for the operation of a private bar or restaurant, areas are either being closed off or they look as though they are closed off,” he said.

Earlier in the evening, the CLF group had stopped by a bar outside the Intercontinental Hotel that the DEP says violates public open space laws. And CLF has filed a lawsuit against a group of developers and the DEP for another waterfront project they say has an inadequate public access plan.

Ben Lynch heads the DEP’s waterways regulation program. He said most waterfront developments willingly meet the public space requirements. And he says when new developments are approved, the public access issue is not negotiable.

“By statute we have to, in order to issue a license for them for a developer to be able to build, the public benefits have to outweigh the private benefits of any site," Lynch said. "And one of the first, probably the first and most important part of any license, is that there be good 24-hour public access.”

Lynch said his office has heard from CLF about the "First Fridays" event at the ICA.

Partygoers at the ICA's event on the Harborwalk.
Meredith Nierman/WGBH

“We will be reaching out to ICA to revisit this issue to make sure that in the future when they want to do these kinds of events that they seek the written approval of the department," he said. "And I should add that were we to give that approval, we would never give the approval to close off the Harborwalk. The Harborwalk is sacrosanct. The Harborwalk has to stay open.”

In response to an inquiry from WGBH News, the ICA responded with a written statement saying the museum has and will continue to provide public access during ICA events, and that they’ve met with security staff to make sure public access is maintained. 

When asked if that will include future "First Fridays" events, they said yes.