In keeping with the theme, a conflict between police and demonstrators over a planned protest against the war in Iraq at the Vineyard Haven post office was resolved peacefully on Wednesday.

The Rev. Alden Besse and Sarah Nevin, co-chairmen of the Vineyard Peace Council, planned the display as part of a national campaign against the war titled Eyes Wide Open. The display features combat boots and professionally made banners that list the number of men and women who have been injured or killed in Iraq.

But when they arrived to set up in front of the post office, a Tisbury police officer approached them and said they were not allowed to hold the event at the post office because it was federal property. The demonstrators tried to move to the sidewalk, but that created conflicts with pedestrians.

Tisbury police chief John Cashin said his department was contacted by a private citizen who asked if the demonstration could be held on the federally-owned property. The chief said he got in touch with the Tisbury postmaster, who said such demonstrations were not permitted.

Chief Cashin said the problem was resolved when Gina Stanley, the owner of the ArtCliff diner, offered space in the restaurant’s parking lot. He said the demonstrators and responding officers resolved the problem peacefully, and there was understanding on both sides.

“We fully support the right of anyone to gather for a peaceful assembly of protest, but we cannot allow the sidewalk to be blocked,” Chief Cashin said.

Reached at his summer home in Chilmark yesterday, Harvard law professor and constitutional scholar Alan M. Dershowitz said the police may or may not have been correct when they moved the protestors.

“There is no one rule [about where a protest may take place],” Mr. Dershowitz said. He continued:

“It depends. The constitutional law today is, it depends. You can’t block traffic or block sidewalks generally — but if there is no other place to protest, then perhaps a court would say it’s permissible to do it. You can’t protest inside a post office, but outside a post office a protest is permissible.”

Mr. Dershowitz also offered his own opinion on the matter.

“In general a place like Martha’s Vineyard ought to err on the side of permitting rather than restricting protest . . . you always ought to err on the side of the First Amendment,” he said.