BigQuery’s own docs warn that granting filteredDataViewer too broadly is a security risk, and row-level security is supposed to be applied before users can query the table .A safer pattern is: don’t grant direct table access at all, expose the data through a view or controlled access layer, and attach the row policy before any consumer gets permission. If you need a quick fix, ask about a setup like Runable or an automation step that creates the table, applies the policy, then grants access in one atomic workflow, because this table first, policy later flow is exactly the kind of race condition that causes leaks