When presidents sign bills into law, they sometimes issue written statements expressing their views on those bills. These written statements are known as "presidential signing statements." Presidents often use signing statements to express their intention not to enforce parts of legislation that they consider to be unconstitutional, or otherwise provide an interpretation of the law as executive branch agencies will be directed to enforce it.
Since at least the Reagan era, scholars, jurists, and others have debated whether presidential signing statements should be considered as legislative history for purposes of interpreting federal statutes. In a recent example, U.S. Supreme Court Justice Antonin Scalia disagreed with his fellow justices' disregard of a signing statement related to the Detainee Treatment Act, Pub. L. No. 109-148, §§ 1005-1006, 119 Stat. 2736 (2005). Hamdan v. Rumsfeld, 548 U.S. 557 (2006) (Scalia dissenting). In March 2009, President Obama issued a memo to the heads of executive departments and agencies in which he opined "In appropriately limited circumstances, [presidential signing statements] represent an exercise of the President's constitutional obligation to take care that the laws be faithfully executed, and they promote a healthy dialogue between the executive branch and the Congress."
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