A federal judge on Tuesday blocked the US Postal Service (USPS) from implementing part of Donald Trump’s executive order that aims to tighten rules for mail-in voting ahead of November midterm elections that will decide control of Congress.

The ruling by US district judge Indira Talwani in Boston effectively expanded on an earlier order she had issued in June that had prevented Trump’s administration from implementing it in 23 mostly Democratic-led states.

Several voting rights groups had urged her to go further and prevent USPS from implementing anywhere in the nation a proposed rule requiring states to provide lists of voters and adopt new balloting procedures before the mail agency would make deliveries.

If states did not comply, USPS would have refused to deliver the ballots. The plaintiffs had contended USPS would have no legal basis for such a refusal.