It is a violation of the Massachusetts Ethics Law for a member of a town community preservation committee who also sits on a private nonprofit board to participate in a decision that grants Community Preservation Act funds to the nonprofit.

This is the opinion of Edgartown town counsel Ronald H. Rappaport, who was recently asked by the town administrator to research the question.

And while the decision was written for Edgartown, it is applicable in every Island town, where community preservation committees have been increasingly active in recent years in doling out taxpayer money to an array of projects, some municipal, some private.

A local option property and recreation tax surcharge that includes matching money from the state, the Community Preservation Act has been adopted by every Island town. As a result, millions have gone to open space preservation, historic renovation and affordable housing. The law that created the act requires that at least 10 per cent of the money collected must go to each of the three enterprises.

The inevitable result has been a co-mingling of public and private money, including for affordable housing projects, many of which are backed by an active trio of nonprofits: the Island Affordable Housing Fund, the Island Housing Trust and the Island chapter of Habitat for Humanity.

In some towns the people who sit on the Community Preservation Committee are also board members for the trust, the fund or Habitat.

In Edgartown, in addition to the community preservation committee, the town recently established an affordable housing trust, which receives monies for affordable housing projects.

In his four-page opinion issued this week, Mr. Rappaport said members of the town CPC and trust committees who wear two hats must recuse themselves or risk violating the state ethics law. “It is my opinion that a member of the CPC or [town] Trust committees is barred from participating in any matter in which either committee decides to award, or to recommend the award of, public funds to a nonprofit on which the committee member sits as a board member,” the town attorney wrote in part.

The decision hinges on two key definitions: whether a CPC member is considered a municipal employee and whether a nonprofit that uses public money to assist with land acquisition and construction, “that is, a project involving the procurement of housing units in the marketplace,” Mr. Rappaport wrote — is considered a business organization.

In both instances he found that the answer was yes. The decision relied in part on a 2007 ethics commission ruling that involved the Vineyard Conservation Society. In that opinion a golf course developer who had a project in front of the Martha’s Vineyard Commission claimed that commission members who also sat on the board of the conservation society were in conflict (the society had taken a position against the golf course). But the ethics commission found that the conservation society, with its central mission of land stewardship, education and conservation, did not meet the definition of a business organization.

By that definition, Island Affordable Housing Fund, the Island Housing Trust and the Island chapter of Habitat for Humanity would be considered a business, in Mr. Rappaport’s opinion.

Town administrator Pamela Dolby said this week that she asked Mr. Rappaport to research the potential conflict question because there has been confusion about the various roles of committee members.

“We just had some questions, and we figured we should get the answers now to make sure there aren’t problems down the road. That’s all this was . . . there is no big smoking gun here. It just means if you sit on a committee and you think there will be a conflict, you don’t participate. If it is an extensive conflict, then you may want to think about stepping aside,” she said.

In Edgartown there is some committee crossover: the chairman of the town affordable housing committee, Janet Hathaway, is also a member of the board of directors for the Island Housing Trust. And community preservation committee member Edward W. Vincent Jr. is also a member of the trust board of directors.

Mrs. Dolby said members of both committees already routinely recuse themselves when there is a potential conflict of interest.

Gazette reporter Jim Hickey contributed to this story.