Democratic state attorneys general on Thursday filed a lawsuit challenging U.S. President Donald Trump's executive order that compels voters to prove they are U.S. citizens and bars states from counting mail-in ballots received after Election Day.

But the lawsuit — brought by the Democratic National Committee, the Democratic Governors Association, and Senate and House Democratic leaders over a recent executive order — argues that the order is unconstitutional, not for voting by noncitizens. Here’s a closer look at the facts.

The lawsuit from 19 Democratic attorneys general calls Trump's executive order an "unconstitutional attempt to seize control of elections."