DA won't charge Walnut Creek officers in fatal shooting of Miles Hall; civil rights attorneys ask AG for help By Lisa Fernandez Contra Costa County DA says police killing won't be prosecuted due to insufficient evidence Miles Hall was killed while suffering from a mental health crisis near his home. Now, the Contra Costa County District Attorney's office says there's insufficient evidence to charge any of the officers involved. KTVU's Brooks Jarosz reports. WALNUT CREEK, Calif. - The Contra Costa County District Attorney’s Office on Friday announced prosecutors will not charge two officers in the 2019 fatal shooting of a Black, schizophrenic man, prompting his family's civil rights attorneys to ask the newly appointed Attorney General to take up the matter.