Supervisor Bilal Mahmood plans legislation to ban uncertified lithium-ion batteries after a Tenderloin apartment fire displaced residents and underscored the risks of low quality electronics.

A former fire marshal helped write San Francisco’s high-rise sprinkler mandate and is now marketing consulting services around exemptions. We can’t call that corruption on the public facts alone, but it sure looks like revolving-door government — and it’s exactly the kind of thing that destroys trust in City Hall.