Cal. RTC § 5909

(a) County assessors may respond to a taxpayer’s written request for a written ruling as to property tax consequences of an actual or planned particular transaction, or as to the property taxes liability of a specified property. For purposes of statewide uniformity, county assessors may consult with board staff prior to issuing a ruling under this subdivision. Any ruling issued under this subdivision shall notify the taxpayer that the ruling represents the county’s current interpretation of applicable law and does not bind the county, except as provided in subdivision (b).

(b) Where a taxpayer’s failure to timely report information or pay amounts of tax directly results from the taxpayer’s reasonable reliance on the county assessor’s written ruling under subdivision (a), the taxpayer shall be relieved of any penalties, or interest assessed or accrued, with respect to property taxes not timely paid as a direct result of the taxpayer’s reasonable reliance. A taxpayer’s failure to timely report property values or to make a timely payment of property taxes shall be considered to directly result from the taxpayer’s reasonable reliance on a written ruling from the assessor under subdivision (a) only if all of the following conditions are met:

(1) The taxpayer has requested in writing that the assessor advise as to the property tax consequences of a particular transaction or as to the property taxes with respect to a particular property, and fully described all relevant facts and circumstances pertaining to that transaction or property.

(2) The assessor has responded in writing and specifically stated the property tax consequences of the transaction or the property taxes with respect to the property.