Supervisor Roger R. Stanton resigned from the Local Agency Formation Commission on Wednesday, becoming the second supervisor to quit the board in the last two months.
Supervisor Thomas F. Riley resigned last month from his position as an alternate to the commission.
Stanton had served on the commission more than seven years. He said he was resigning because he had served long enough and the work was taking an inordinate amount of his staff's time.
The commission is made up of two supervisors, two city representatives and a member of the public. There is also an alternate for each member.
Supervisor Harriett M. Wieder, newly installed chairwoman of the Board of Supervisors, is responsible for appointing the board's representatives to Lafco and other county boards.
But she said Wednesday that choosing new members for the commission has been made difficult by a state law that restricts campaign contributions its members can receive. The law prohibits commission members from participating in votes involving individuals or companies that have donated more than $250 to their campaigns.
Wieder said the law made it particularly awkward for Supervisors Gaddi H. Vasquez and Stanton to serve on the commission because both are up for reelection this year and thus have raised a lot of money in campaign contributions.
"It's not very practical . . . for Stanton and Vasquez both," she said. "This particular appointment is a problem one because of the restrictions on it."
Stanton has expressed interest in running for the 40th District congressional seat held by Rep. Robert E. Badham (R-Newport Beach). Badham announced earlier this week that he will not seek reelection.
But Stanton said the state campaign-contribution law did not affect his decision to resign.