Organizations that lobby the city are allowed to give elected officials free admission to events they host, the city’s Conflicts of Interest Board said yesterday in an advisory opinion.

The city in 2006 banned gifts to elected officials and civil servants from lobbyists as part of a larger bill to limit the influence of City Hall lobbyists, but the specifics of the law were unclear to at least two nonprofit organizations that contacted the city for clarification.

The organizations, which were not named in the opinion, are listed as lobbyists because at least some of their employees lobby the city as part of their job.

The Metropolitan Museum of Art, for example, one of several cultural institutions listed as a lobbying organization with the city, is allowed to invite elected officials and city employees to museum functions and fund-raisers without violating the law under the opinion.

The opinion does not explain if the same rules would apply to lobbying firms. A lawyer for the Conflicts of Interest Board would not provide more clarity, deferring to the opinion.

A former parks commissioner who is the director of New York Civic, Henry Stern, said it is difficult to judge which invitations are appropriate for elected officials to accept and which are not.

“In the absence of being able to make more specific delineations of what’s good and what’s bad, I would say it’s alright to let them in for free,” he said. “Strict conflict regulations hobble the good guys that are trying to do their jobs, whereas the bad guys are going to ignore them.”