The lawyer for Kilmar Armando Abrego Garcia, a Maryland man mistakenly deported in the Trump administration’s roundup of alleged gang members, said he expects his client to be returned in the coming weeks.

“I have every expectation that the Supreme Court will rule quickly and will rule in our favor, because when push comes to shove, this is not an exceptional case. The only exceptional thing has been the way in which the government has dug in its heels on making right what they messed up," attorney Simon Sandoval-Moshenberg told ABC News.

"Jennifer is really worried. She expects and I expect that we are going to get him back," he added, referring to Abrego Garcia’s wife.

U.S. District Judge Paula Xinis on Sunday ordered the Trump administration to return Abrego Garcia by midnight on Monday.

“Neither the United States nor El Salvador have told anyone why he was returned to the very country to which he cannot return, or why he is detained at CECOT,” Xinis wrote in her ruling, referring to the El Salvador prison where Abrego Garcia has been detained.

“That silence is telling. As Defendants acknowledge, they had no legal authority to arrest him, no justification to detain him, and no grounds to send him to El Salvador — let alone deliver him into one of the most dangerous prisons in the Western Hemisphere.”

Supreme Court Chief Justice John Roberts later halted the judge's decision with a temporary administrative stay.

Abrego Garcia is a Salvadoran national who fled due to political discourse in 2011.

A Trump administration official said he was removed due to an “administrative error.”

A group of Senate Democrats earlier this week urged Homeland Security Secretary Kristi Noem and Immigration and Customs Enforcement acting Director Todd Lyons to swiftly return Abrego Garcia, who was detained after a traffic stop.

“It is unacceptable that anyone would be deported without proper due process, especially where an immigration judge has granted the individual protected status that explicitly prohibits his return to El Salvador,” they wrote in a Tuesday letter.

“We demand that the Administration bring Mr. Abrego Garcia home immediately,” the letter continued.