users, criminally misused by trusted insiders or abused by government agents. David Addington – at that time legal counsel to former Vice President Dick Cheney – was reported to be the author of the controlling legal and technical documents for the program. Legal issues While the dispute over the NSA program was waged on multiple fronts, the legal dispute pitted Bush and Obama administrations against opponents in Congress and elsewhere. Supporters claimed that the President's Constitutional duties as commander in chief allowed him to take all necessary steps in wartime to protect the nation and that AUMF activated those powers. Opponents countered by claiming that instead that existing statutes (predominantly FISA) circumscribed those powers, including during wartime. Formally, the question can be seen as a disagreement over whether Constitutional or statutory law should rule in this case. As the debate continued, other arguments were advanced. Constitutional issues The constitutional debate surrounding the program is principally about separation of powers. If no "fair reading" of FISA can satisfy the canon of avoidance, these issues must be decided at the appellate level. In such a separation of powers dispute, Congress bears burden of proof to establish its supremacy: the Executive branch enjoys the presumption of authority until an Appellate Court rules against it. Article I and II Whether "proper exercise" of Congressional war powers includes authority to regulate the gathering of foreign intelligence is a historical point of contention between the Executive and Legislative branches. In other rulings has been recognized as "fundamentally incident to the waging of war". "Presidential Authority to Conduct Warrantless Electronic Surveillance to Gather Foreign Intelligence Information", published by The Congressional Research Service stated: The same report repeats the Congressional view that intelligence gathered within the U.S. and where "one party is a U.S. person" qualifies as domestic in nature and as such is within their purview to regulate, and further that Congress may "tailor the President's use of an inherent constitutional power": Fourth Amendment The Bush administration claimed that the administration viewed the unanimity of pre-FISA Circuit Court decisions as vindicating their argument that warrantless foreign-intelligence surveillance authority existed prior to and subsequent to FISA and that this derived its authority from the Executive's inherent Article II powers, which may not be encroached upon by statute. District Court findings Even some legal experts who agreed with the outcome of ACLU v. NSA criticized the opinion's reasoning. Glenn