Deported Dreamer Juan Manuel Montes claims he was minding his own business on a street in Calexico, Calif., the night of Feb. 17 when Border Patrol agents approached him, took him into custody, and, a few hours later, in the wee hours of the morning of February 18, deported him to his native Mexico.

"At approximately 1:00 a.m. or later, CBP officers walked Mr. Montes to the U.S.-Mexico border (near Mexicali, Baja California) and physically removed him from the United States despite his DACA status," Montes' lawyers wrote in a lawsuit filed against U.S. Customs and Border Protection.

"You can't do these things in the middle of the night," added Montes attorney Karen Tumlin, of the National Immigration Law Center, during a conference call with reporters last week.

The Department of Homeland Security, which oversees Border Patrol, says none of that happened. "There are no records or evidence to support Montes' claim that he was detained or taken to the Calexico Port of Entry on Feb. 18, 2017," DHS said last week. The first time CBP agents encountered Montes, officials said, was the next day, Feb. 19, when they took him into custody shortly after he climbed the border fence from Mexico into the United States.

Montes invalidated his Dreamer status, officials say, by leaving the U.S. without authorization and then attempting to re-enter illegally.

Now there is another question about Montes' story. Officials say CBP does not deport people "in the middle of the night," and that there is, in fact, a policy forbidding Border Patrol officers from doing so.

DHS arrangements for the repatriation of Mexican nationals, worked out between the U.S. and Mexico and available on the internet, indicate that repatriation is allowed for adults and accompanied minors at the Calexico port of entry between 6:00 a.m. and 10:00 p.m. daily.

Ralph DeSio, a spokesman for CBP in San Diego, confirmed that the statement of policy is accurate. "Yes, the information is correct," he said via email. "The Mexican authorities have a lock on the repatriation gate. It is impossible for us to open that gate to repatriate someone unless the Mexican authorities are present to unlock their side of the gate."

Nighttime deportations have been a sensitive issue in the past. Some cities into which a person is released are dangerous in the middle of the night. Businesses aren't open. It's harder to get around. So the U.S. curtailed the practice. "Since last year, we have moved away from night repatriations," Homeland Security Secretary Jeh Johnson told Congress in 2015.

Now, Montes claims he was deported "in the middle of the night." And Border Patrol officials contend no deportations take place at that time. The bottom line is that there are more questions swirling around a case which some activists have wanted to make a key element of the resistance to President Trump's immigration policy.

Karen Tumlin did not respond to emails requesting comment.