A sunshine ordinance is a government agency's self-imposed improvement on state sunshine laws like the Brown Act, the California Public Records Act or even the rules governing access to court administrative records. The improvement consists in filling in these minimal laws' gaps, compensating for their limitations, or lowering their barriers.  In adopting a sunshine ordinance (it needn’t literally be an ordinance—a bylaw or other policy commitment will do), a government agency increases rights of access to its meetings and records, enhances citizens’ rights to participate in its processes, or both.
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Sunshine Ordinance Wiki