U.S. law[edit]
Further information: Doe v. Bush, US Constitution and US law
The United States Court of Appeals for the First Circuit refused to review the legality of the invasion in 2003, citing a lack of ripeness.
In early 2003, the Iraq Resolution was challenged in court to stop the invasion from happening. The plaintiffs argued that the President does not have the authority to declare war. The final decision came from a three-judge panel from the US Court of Appeals for the First Circuit which dismissed the case. Judge Lynch wrote in the opinion that the Judiciary cannot intervene unless there is a fully developed conflict between the President and Congress or if Congress gave the President "absolute discretion" to declare war.[30]
Similar efforts to secure judicial review of the invasion's legality have been dismissed on a variety of justiciability grounds.
Legal debates - U.N. security council resolutions[edit]
Debate about the legality of the 2003 invasion of Iraq under international law, centers around ambiguous language in parts of U.N. Resolution 1441 (2002).[31] The U.N. Charter in Article 39 states: "The Security Council shall determine the existence of any threat to the peace, breach of the peace, or act of aggression and shall make recommendations, or decide what measures shall be taken in accordance with Articles 41 and 42, to maintain or restore international peace and security".
The position of the U.S. and U.K. is that the invasion was authorized by a series of U.N. resolutions dating back to 1990 and that since the U.N. security council has made no Article 39[32] finding of illegality that no illegality exists.
Resolution 1441 declared that Iraq was in "material breach" of the cease-fire under U.N. Resolution 687 (1991), which required cooperation with weapons inspectors. The Vienna Convention on the Law of Treaties states that under certain conditions, a party may invoke a "material breach" to suspend a multilateral treaty. Thus, the U.S. and U.K. claim that they used their right to suspend the cease-fire in Resolution 687 and to continue hostilities against Iraq under the authority of U.N. Resolution 678 (1990), which originally authorized the use of force after Iraq invaded Kuwait.[33] This is the same argument that was used for Operation Desert Fox in 1998.[34] They also contend that, while Resolution 1441 required the UNSC to assemble and assess reports from the weapons inspectors, it was not necessary for the UNSC to reach an agreement on the course of action. If, at that time, it was determined that Iraq breached Resolution 1441, the resolution did not "constrain any member state from acting to defend itself against the threat posed by Iraq".[35]
It remains unclear whether any party other than the Security Council can make the determination that Iraq breached Resolution 1441, as U.N. members commented that it is not up to one member state to interpret and enforce U.N. resolutions for the entire council.[36] In addition, other nations have stated that a second resolution was required to initiate hostilities.[37] Some have asserted that the war was an illegal war of aggression, and Kofi Annan, former United Nations Secretary-General, expressed the belief that the war in Iraq was an "illegal act that contravened the U.N. charter."[38]