Boston Mayor Marty Walsh signed an executive order on Monday that he says will bring needed transparency and accountability to Boston’s embattled Zoning Board of Appeals (ZBA) which decides whether to grant relief from city zoning codes for everything from major developments to residential roof decks.

Walsh said months ago that change was coming to the ZBA, which has been operating under the shadow of scandal since longtime City Hall employee John Lynch pleaded guilty to taking a bribe from a developer in 2017 in exchange for attempting to influence an unnamed ZBA member’s vote.

No current or former ZBA members were accused of wrongdoing. The charges to which Lynch pleaded did not allege that any members of the ZBA were swayed by him,or that any members were aware of the criminal scheme.

An independent audit of the ZBA, commissioned by Mayor Walsh and completed last fall, found no evidence that any “current” members of the ZBA had acted improperly.

But the scandal put a spotlight on the board and the potential for, or appearance of, conflict of interest on the board, which has operated in relative obscurity.

In September, WGBH News reported that a former ZBA member and real estate broker who resigned shortly after Lynch's guilty plea, Craig Galvin, had on multiple occasions voted to approve zoning relief for properties whose sale he later brokered.

Walsh’s executive order is aimed largely at clarifying and tightening ethics rules for ZBA members and staff.

Emphasizing that the city found no evidence of actual impropriety on the board, Walsh said that the new rules are nonetheless crucial to restore trust in the agency.

“The board must operate with the highest standards of professionalism, ethics and accessibility,” he said.

The newly propagated rules require that ZBA members disclose private real estate interests at the time of their appointment; prohibits members from participating or voting on any matter before the ZBA in which they hold a personal interest or have had an interest the past five years; and prohibits members from engaging in business involving any properties they’ve voted on for two years going forward.

ZBA members and staff will also be required to complete ethics training.

“We want to use this moment as an opportunity to strengthen our board, and to take away any potential conflicts that could be there,” Walsh said.

“The executive order today moves us forward and I thank Mayor Walsh for listening to the need for action,” Boston City Councilor Lydia Edwards said .

Edwards, who said she is moving forward with a a City Council hearing on potential ZBA reforms Tuesday, said she still wants to discuss possible changes to ZBA terms and the way the board is organized — changes which would require state approval of a home rule petition.

Under Massachusetts law, Boston’s mayor must appoint ZBA members nominated by specific industry groups, including one seat reserved for nomination by a real estate industry group.