"There's a lot we don't know. We just want to stop it," added Cotchett.
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Richmond mayor Tom Butt says much of the city's federal money goes to its housing authority, about $27 million per year.
Richmond Police Chief Allwyn Brown says the city's sanctuary policy helps his department.
"Providing safety in a city really does require actively engaged residents who can interact with police, without fear of other issues," said Brown.
In Martinez, demonstrators marched into the Contra Costa County building to the office of Sheriff David Livingston, who opposes senate bill 54, which would make California a sanctuary state.
Livingston was unavailable, but a spokesman explained the sheriff's opposition to SB54.
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"Many state sheriffs are opposed to it. They believe it goes too far and it could compromise public safety. Specifically, it would prevent law enforcement from even talking to ICE," said Jimmy Lee, a spokesperson for the sheriff's office.
SB54 will be heard on the senate floor in Sacramento on Monday.
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