Yesterday's story on the possibilities for a presidential signing statement on Guantanamo led to some additional good reporting by colleagues at The New York Times, The Washington Post and elsewhere. And to some sharp analysis from law professors including Jack Goldsmith and Bobby Chesney and by national security writers including Marcy Wheeler and Adam Serwer.

I invite interested readers to check out their work, especially discussions about the constitutionality of the provisions, the implications for the president's policies and the politics -- how those on the left and right of this issue view the possibility of a signing statement and other tools at the president's disposal. New York Times reporter Charlie Savage, an expert on signing statements, yesterday confirmed the details in our story, noting that the president could bypass legislation that would all but dismantle his goals to prosecute some Guantanamo detainees.

Today, Savage advances it further, reporting that a current draft statement, as described to him by a White House official, stops short of claiming that the provisions in a spending bill related to Guantanamo are unconstitutional. But Savage notes that the option to go further is still on the table and being hotly debated. And he quotes Kate Martin, director of the Center for National Security Studies, arguing that the language in the spending bill exceeded its constitutional authority.

"I think that Congress restricting his discretion about where to prosecute people is unconstitutional, and I think he should make that clear," Martin told the Times.

Representative Candace Miller, a Republican from Michigan, who serves on the House Homeland Security committee, urged President Obama in a statement not to challenge the provisions and to abandon plans to move detainees to U.S. soil.

Two former administration officials who are close to the debate both suggested the White House was likely to oppose the provisions on policy grounds, rather than legal grounds. One former official said that while policymakers inside the Obama administration have been frustrated and angered by the provisions, and are pushing for a repudiation, Obama's legal advisers are uncertain that he can claim the provisions as unconstitutional.

The president will likely sign the bill next week, officials said, and could issue the statement alongside it.

A story in Politico today by Laura Rozen notes the pending White House departure of staff member Dave Rapallo who has spent the last year coordinating Guantanamo policies. Rozen interprets the move as the White House waving a white flag on its Guantanamo strategy in the face of the legislation. Rapallo is the latest Guantanamo adviser to depart the administration. Last year, White House Counsel Greg Craig left after months of efforts to deal with Guantanamo and detention issues.

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