The U.S. Postmaster General stated the Postal Service could hold back mail‑in ballots in any jurisdiction that does not share its voter data.
The move follows a new rule that requires states to disclose their mail voting lists.
If a state refuses, ballot delivery could be postponed or stopped during an election.
The Postal Service states the requirement is needed to keep mail processing efficient.
Officials note the rule would give the agency the information it needs to sort and deliver ballots on time.
Critics alert the action could affect voters in tight races.