Boston zoning board of appeals member Craig Galvin has submitted his resignation and former head of inspectional services William “Buddy” Christopher is on a leave of absence amid a continuing federal probe of development review at Boston City Hall.

Christopher on Friday stepped aside from his current job as adviser to Mayor Marty Walsh on the South End drug corridor. Walsh has appointed a former federal prosecutor, Brian Kelly, to investigate the city’s permitting system following bribery charges against John Lynch, former assistant director of real estate at the Economic Development Industrial Corp., a sibling agency of the Boston Planning and Development Agency.

Federal prosecutors say Lynch accepted a $50,000 bribe from a real estate developer to influence an unidentified ZBA member’s vote on a building project. Lynch, who faces up to 57 months in prison under a plea agreement, has a court appearance Thursday afternoon. Hank Brennan, a Boston lawyer whose clients have included the late organized crime boss James “Whitey” Bulger, is representing Lynch.

Galvin, partner at Dorchester real estate agency Galvin Group, has been the real estate industry appointee to the ZBA since 2016.

“Due to the broad role of a zoning board member and as the board moves forward in their next chapter, Mr. Galvin felt it best to tender his resignation,” according to a statement released to The Boston Globe on Sunday.

Christopher is a Dorchester architect. The firm he co-founded inn 2005, Roche-Christopher Architecture, has designed projects reviewed by the BPDA and the ZBA. He stepped down from the firm and handed over leadership to his son after being named commissioner of inspectional services in 2014.