A federal appeals court tentatively halted a ruling that blocked legislation authorizing the government to indefinitely detain without trial individuals, including U.S. citizens, who are deemed to "substantially support" groups "engaged in hostilities against the United States or its coalition partners."

The decision (.pdf) by the 2nd U.S. Circuit Court of Appeals came late Monday in response to an an emergency petition (.pdf) by the Obama administration earlier that day. The administration called a lower court's ruling striking down the law a threat to national security. A New York federal judge last week found the rule to be unconstitutional as it was so vague it could apply to U.S. citizens and journalists exercising their constitutional rights, and the government immediately appealed.

Circuit Judge Raymond Lohier, appointed by President Barack Obama in 2010, issued the temporary stay of enforcement late Monday. Procedurally, the government's emergency petition moves to a motions panel, which will decide on September 28 whether to keep the stay alive while the issue is litigated on appeal in the New York-based appeals court. Lohier did not comment in his brief order.

Those subject to indefinite detention under the 2011 National Defense Authorization Act include:

A person who was part of or substantially supported al-Qaeda, the Taliban, or associated forces that are engaged in hostilities against the United States or its coalition partners, including any person who has committed a belligerent act or has directly supported such hostilities in aid of such enemy forces.

The act is a broad package of legislation that also includes both authorizations for military spending as well as additional, non-spending legislation. In his Dec. 31 signing statement, President Barack Obama said that "my administration will not authorize the indefinite military detention without trial of American citizens."