Greenwald argued that the perceived flaws in the opinion in fact reflect the Department of Justice's refusal to argue the legal merits of the program (they focused solely on standing and state secrets grounds). FISA practicality FISA grants FISC the exclusive power to authorize surveillance of US persons as part of foreign intelligence gathering and makes no separate provision for surveillance in wartime. The interpretation of FISA's exclusivity clause is central because both sides agree that the NSA program operated outside FISA. If FISA is the controlling authority, the program is illegal. The "no constitutional issue" critique is that Congress has the authority to legislate in this area under Article I and the Fourth Amendment, while the "constitutional conflict" critique claims that the delineation between Congressional and Executive authority in this area is unclear, but that FISA's exclusivity clause shows that Congress had established a role for itself in this arena. The Bush administration argued both that the President had the necessary power based solely on the Constitution and that conforming to FISA was not practical given the circumstances. Assistant Attorney General for Legislative Affairs, William Moschella, wrote: FBI Special Agent Coleen Rowley, in her capacity as legal counsel to the Minneapolis Field Office recounted how FISA procedural hurdles had hampered the FBI's investigation of Zacarias Moussaoui (the so-called "20th hijacker") prior to the 9/11 attacks. Among the factors she cited were the complexity of the application, the amount of detailed information required, confusion by field operatives about the standard of probable cause required by the FISC and the strength of the required link to a foreign power. At his appearance before the Senate Judiciary Committee in June 2002, FBI Director Robert Mueller responded to questions about the Rowley allegations, testifying that unlike normal criminal procedures, FISA warrant applications are "complex and detailed", requiring the intervention of FBI Headquarters (FBIHQ) personnel trained in a specialized procedure (the "Woods" procedure) to ensure accuracy. The Supreme Court made no ruling on this question. However, on June 29, 2006, in Hamdan, the Supreme Court rejected an analogous argument. Writing for the majority, Justice John Paul Stevens, while ruling that "the AUMF activated the President's war powers, and that those powers include the authority to convene military commissions in appropriate circumstances" (citations omitted), held that nothing in the AUMF language expanded or altered the Uniform Code of Military Justice (which governs military commissions.) Stevens