The committee says the practice raises concerns about the mayor's control and influence.
"Requiring an appointee or a nominee to provide an undated resignation letter at the time of appointment undermines charter protections for commissioners against at will removal by the appointing authority," said San Francisco supervisor Dean Preston," adding, "raises significant concerns about the level on control that the mayor has over commissioners."
"I think it's an abuse of power," he said. "Had anyone else done this there would be calls to have them removed from office."
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On Sept. 27, Preston referred to the mayor's practice of using undated resignation letters as "coercive" and said he had directed the City Attorney's Office to draft an ordinance prohibiting their use.
"Requiring undated resignation letters from nominees for Commissions is completely out of line and inconsistent with our City's Charter. As Chair of GAO, I am committed to uncovering all of the facts here and making sure this never happens again," Preston's office said in September.
At Tuesday's meeting, Supervisor Preston says the charter currently doesn't lay out consequences for a situation such as this, but did mention there's legislation in the works to prevent it.
Mayor Breed's office released a statement saying those resignation letters were intended for "dire situations'" and that none has been used over the last four years.
The mayor's office says the practice will be discontinued and existing letters will be rescinded.
Bay City News contributed to this report
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