Richard all these are linked to here. http://news.lib.uchicago.edu/blog/2011/05/
Did American forces comply with applicable law when they killed Osama bin Laden? Yes, according to Law School Professor Aziz Huq. In a recent radio interview (Does the death of Osama bin Laden change the legal game?), Professor Huq states that the killing of bin Laden "falls within the domain of permissible force that can be used by the [U.S.] military[Rules of Engagement] and doesn't fall within the prohibition on assassinations that applies to civilian agencies [Executive Order]." Other commentators have also weighed in on the issue. Here are links to some selected legal analyses (see also the Lawfare national security blog for summaries of commentary on the legality of killing Osama bin Laden):

■John B. Bellinger III, Bin Laden Killing: The Legal Basis (Council on Foreign Relations, May 2, 2011)
■bin Laden Slaying: Was It Legal? (Rebecca Baker reporting on Pace international law symposium, May 6, 2011)
■Thomas Darnstädt, Justice, American Style: Was Bin Laden's Killing Legal? (SPIEGEL ONLINE, May 3, 2011)
■Ashley S. Deeks, Pakistan's Sovereignty and the Killing of Osama Bin Laden (ASIL Insights, May 5, 2011)
■Kevin Jon Heller, Quick Thoughts on UBL's Killing, and a Response to Lewis (Opinio Juris, May 4, 2011)(legal under international humanitarian law (IHL))
■In bin Laden killing, legal clarity (National Law Journal, May 9, 2011; quotes U.S. Attorney General, Eric Holder, Jr.)(available via LexisNexis)
■Raffi Khatchadourian, Bin Laden: The Rules of Engagement (The New Yorker, May 4, 2011) (includes links to related magazine and newspaper articles)
■Fiona de Londras, Killing Osama bin Laden; Doing Justice? (IntlawGrrls, May 4, 2011)
■Marko Milanovic, When to Kill and When to Capture, (EJIL: Talk!, May 6, 2011)
■Marko Milanovic, Was the Killing of Osama bin Laden Lawful? (EJIL: Talk!, May 2, 2011)
■Mary Ellen O'Connell, The bin Laden aftermath: Abbottabad and international law (Foreign Policy, May 4, 2011)
■Mary Ellen O'Connell, The Death of bin Laden As a Turning Point (Opinio Juris, May 3, 2011)
■Geoffrey Robertson, Why it's absurd to claim that justice has been done (The Independent, May 3, 2011)
■Ben Saul, Delivered from evil…to a minefield of law and consequence (The Drum Opinion, ABC, May 4, 2011)
■Jeffrey Toobin, Killing Osama: Was It Legal? (The New Yorker, May 2, 2011)
■Beth Van Schaack, Assassination under International & Domestic Law (IntLawGrrls, May 2, 2011) (includes links to some relevant documents)
■Debra Cassens Weiss, Disclosure that Bin Laden Was Unarmed Has Critics Claiming a Violation of International Law (ABA Journal, May 4, 2011)
■What Was the Legal Basis for the Bin Laden Strike? (BLT, Blog of the Legal Times, May 2, 2011