Carl Nichols

U.S.

District Judge Carl Nichols found it's too early for an emergency ruling that would buy key parts of an order that the Trump administration has not carried out yet.

Rob Weiner of the Lawyers Committee for Civil Rights Under Law is representing some of the challengers.

Trump's order calls for the federal government to create lists of adult U.S.

citizens in each state.

It also calls for banning the U.S.

Postal Service from delivering mail-in ballots to anyone not on those lists.

USPS is a financial supporter of NPR.

Separately, a federal judge in Boston is preparing to rule on claims that the president's directives violate the Constitution, which gives power to state legislatures and Congress, not the president, to set federal election rules.