"We are making legal preparations if the president tries to break the law," Ryan said on Wednesday.
The Wisconsin Republican said what "boggles" his mind is that Obama would be directing the military to knowingly break the law by transferring prisoners from Guantanamo Bay to U.S. prisons in an effort to close the detention center.
"Our law is really clear," Ryan said, adding that it was Democrats who first wrote the language barring detainees from coming to American soil.
Those provisions have been codified annually in the National Defense Authorization Act, and Ryan pointed to the bill and the strong bipartisan support it enjoys as evidence that there's a majority in Congress who would vote to override an Obama veto of not closing Guantanamo.
That may be overstating the case, of course, as the last time the House voted on an amendment during the NDAA debate to close the detention center, the proposal was rejected 174-249, more than 30 votes short of the two-thirds majority required to make law without the president's signature.
But Ryan's vow to pass legislation to keep Guantanamo open is far less serious a challenge than the legal one he's threatening.
A GOP leadership aide told The Huffington Post on Wednesday that the House had already, under Ryan's direction, “entered into a contract for advice concerning legal options should the president unlawfully transfer Gitmo detainees in an amount up to 150k.”
While that certainly wouldn't be enough to actually sue the president, it is a start in building the legal argument that will be made to make the public relations case.
House Republicans have already shown a willingness to sue Obama. A judge ruled in September that they had standing to sue the president over his selective implementation of the health care law, and they have open cases on his executive action on immigration and the administration's lack of compliance on subpoenas related to the "Fast and Furious" investigation.
Those cases, however, are far more tenuous than a potential legal challenge on Guantanamo. As Ryan insisted, the law is clear that the president can't transfer detainees to American soil. The military can't even spend a dime to modify a detention facility in preparation for a move.
It's unclear how exactly Obama will move forward with his Guantanamo plan. He was emphatic Tuesday that he wants to close the prison, something he pledged to do in his first days as president as a candidate in 2008.
But his administration has acknowledged that doing so without Congress' consent would be unlawful. And if Obama does try to fulfill his Guantanamo promise, it looks like House Republicans are ready to take it to a judge.
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