Both the House and Senate have adjourned for the weekend, all but ensuring that the government shutdown be the longest in U.S. history.

The big picture: 800,000 federal workers didn't receive their paychecks Friday, on Day 21 of the shutdown. At least three federal employee organizations are suing the Trump administration for unlawfully depriving workers of earned wages without due process. President Trump has suggested that if he is unable to strike a deal with Congress to reopen the government, he is likely to declare a national emergency in order to build his border wall.

Go deeper: Shutdown, Day 21 — "Payday without pay"