The renewal of military commission proceedings against Khalid Sheik Mohammad and four others for their alleged involvement in the 9/11 terrorist attacks has focused renewed attention on the differences between trials in federal court and those conducted by military commission. The decision to try the defendants in military court required a reversal in policy by the Obama Administration, which had publicly announced in November 2009 its plans to transfer the five detainees from the U.S. Naval Station in Guantanamo Bay, Cuba, into the United States to stand trial in the U.S. District Court for the Southern District of New York for criminal offenses related to the 9/11 attacks. The Administration's plans to try some Guantanamo detainees in federal civilian court proved controversial, and Congress responded by enacting funding restrictions which barred any non-citizen held at Guantanamo from being transferred into the United States for any purpose, including prosecution. These restrictions, which have been extended for the duration of FY2014, effectively make military commissions the only viable option for trying detainees held at Guantanamo for the foreseeable future, and have resulted in the Administration choosing to reintroduce charges against Mohammed and his co-defendants before a military commission. While military commission proceedings have been instituted against a number of suspected enemy belligerents held at Guantanamo, the Obama Administration has opted to bring charges in federal criminal court against many terrorist suspects held at locations other than Guantanamo. On July 5, 2011, Somali national Ahmed Abdulkadir Warsame was brought to the United States to face terrorism-related charges in a civilian court, after having reportedly been detained on a U.S. naval vessel for two months for interrogation by military and intelligence personnel. Some argued that Warsame should have remained in military custody abroad and face trial before a military commission, while others argued that he should have been transferred to civilian custody immediately. Similar controversy also arose regarding the arrest by U.S. civil authorities and subsequent prosecution of Umar Farouk Abdulmutallab and Faisal Shahzad, who some argued should have been detained and interrogated by military authorities and tried by military commission. This report provides a brief summary of legal issues raised by the choice of forum for trying accused terrorists and a chart comparing authorities and composition of the federal courts to those of military commissions. A second chart compares selected military commissions rules under the Military Commissions Act (MCA), as amended by the Military Commissions Act of 2009, to the corresponding rules that apply in federal court. This chart follows the same order and format used in CRS Report RL31262, Selected Procedural Safeguards in Federal, Military, and International Courts , to facilitate comparison with safeguards provided in international criminal tribunals. For similar charts comparing military commissions as envisioned under the MCA, as passed in 2006, to the rules that had been established by the Department of Defense (DOD) for military commissions and to general military courts-martial conducted under the Uniform Code of Military Justice (UCMJ), see CRS Report RL33688, The Military Commissions Act of 2006: Analysis of Procedural Rules and Comparison with Previous DOD Rules and the Uniform Code of Military Justice , by [author name scrubbed]. For a comparison of the rules established by the MCA 2006 with those found in the MCA 2009 and to the rules that apply to courts martial under the UCMJ, see CRS Report R41163, The Military Commissions Act of 2009 (MCA 2009): Overview and Legal Issues , by [author name scrubbed]. For additional analysis of issues related to the disposition of Guantanamo detainees, including possible trials in federal or military courts, see CRS Report R40139, Closing the Guantanamo Detention Center: Legal Issues , by [author name scrubbed] et al. On January 22, 2009, President Barack Obama issued an executive order requiring that the Guantanamo detention facility be closed no later than a year from the date of the order. The order established a task force ("Guantanamo Task Force") to review all Guantanamo detentions to assess whether each detainee should continue to be held by the United States, be transferred or released to another country, or be prosecuted by the United States for criminal offenses. Ongoing military commissions were essentially halted during this review period, although some pretrial proceedings continued to take place. One detainee, Ahmed Ghailani, was transferred in June 2009 to the Southern District of New York for trial in federal court on charges related to his alleged role in the 1998 East Africa Embassy bombings, and was subsequently convicted and sentenced to life imprisonment. President Obama's Detention Policy Task Force issued a preliminary report July 20, 2009, reaffirming that the White House considers military commissions to be an appropriate forum for trying some cases involving suspected violations of the laws of the war, although federal criminal court would be the preferred forum for any trials of detainees. The disposition of each case referred for criminal prosecution is to be assigned to a team comprised of DOJ and DOD personnel, including prosecutors from the Office of Military Commissions. The report also provided a set of criteria to govern the disposition of cases involving Guantanamo detainees. In addition to "traditional principles of federal prosecution," the protocol identifies three broad categories of factors to be taken into consideration: Strength of interest, namely, the nature and gravity of offenses or underlying conduct; identity of victims; location of offense; location and context in which individual was apprehended; and the conduct of the investigation. Efficiency, namely, protection of intelligence source and methods; venue; number of defendants; foreign policy concerns; legal or evidentiary problems; efficiency and resource concerns. Other prosecution considerations, namely, the extent to which the forum and offenses that can be tried there permit a full presentation of the wrongful conduct, and the available sentence upon conviction. On November 13, 2009, Attorney General Holder announced the decision to transfer five "9/11 conspirators" to the Southern District of New York to stand trial, and charges that had previously been brought against these individuals before military commissions were withdrawn without prejudice in January 2010. On January 22, 2010, the Guantanamo Task Force issued its final report concerning the appropriate disposition of each detainee held at Guantanamo. The Task Force concluded that 36 detainees remained subject to active criminal investigations or prosecutions; 48 detainees should remain in preventive detention without criminal trial, as they are "too dangerous to transfer but not feasible for prosecution"; and the remaining detainees may be transferred, either immediately or eventually, to a foreign country. The Administration's plans to bring Khalid Sheik Mohammed and other Guantanamo detainees into the United States proved controversial. Beginning in 2009, Congress began placing funding restrictions in annual appropriations and authorization measures to limit executive discretion to transfer or release Guantanamo detainees into the United States. Because no civilian court operates at Guantanamo, these limitations have effectively made military commissions the only viable option for trying Guantanamo detainees for criminal activity for the foreseeable future. In March 2011, Secretary of Defense Robert Gates announced that the government would resume the filing of charges before military commissions at Guantanamo. Shortly thereafter, Attorney General Eric Holder announced the Obama Administration's reversal of its decision to bring Khalid Sheik Mohammed and his alleged co-conspirators into the United States to face trial in federal court, and stated that they would instead be tried before a military commission at Guantanamo. In April 2012, charges were referred to a military commission against Khalid Sheikh Mohammed, Walid Bin Attash, Ramzi Bin Al Shibh, Ali Abdul-Aziz Ali, and Mustafa Ahmed Al Hawsawi for their alleged involvement in the 9/11 attacks. In October 2012, the U.S. Court of Appeals for the D.C. Circuit, in its first case of an appeal from a military commission conviction, reversed the conviction of Salim Hamdan after determining that Congress did not intend for the offenses it defined in the MCA to apply retroactively ( Hamdan II ). Because the court agreed that the crime of material support for terrorism did not exist as a war crime under the international law of war at the time the relevant conduct occurred (a requirement under the military commissions statute in effect at the time ), it vacated the decision below of the Court of Military Commissions Review (CMCR), which had unanimously affirmed Hamdan's conviction. Some have noted the prevalence of the charge of material support for terrorism in military commission cases to date and question the continued viability of the military commission system in light of this decision. The government did not appeal the decision to the Supreme Court. Instead, the government is appealing the second CMCR appeal of a final verdict, Al Bahlul v. United States. When that case reached the D.C. Circuit on appeal, the government essentially asked the appellate court to overturn Al Bahlul's conviction on the basis that Hamdan II provided binding precedent on the question presented, namely, the validity of convictions for conspiracy, solicitation, and material support of terrorism for conduct preceding passage of the Military Commissions Act (MCA) in 2006. ( Hamdan II did not address conspiracy or solicitation, but the government conceded that these offenses do not constitute universally recognized violations of the international law of war.) The court complied with the request in a per curiam order. The government sought and was granted a rehearing en banc in the Bahlul case. U.S. law provides for the trial of suspected terrorists, including those captured abroad, in several ways. Those who are accused of violating specific federal laws are triable in federal criminal court. Provisions in the U.S. Criminal Code relating to war crimes and terrorist activity apply extraterritorially and may be applicable to some detainees. Those accused of violating the law of war or committing the offenses enumerated in the Military Commissions Act (MCA), as amended by the Military Commissions Act of 2009, may be tried by military commissions under the MCA, or by general court-martial under the UCMJ. The procedural protections afforded to the accused in each of these forums may differ. The MCA authorizes the establishment of military commissions with jurisdiction to try alien "unprivileged enemy belligerents" for offenses made punishable by the MCA or the law of war. Notwithstanding the recent amendments to the MCA, which generally enhance due process guarantees for the accused, critics continue to question their constitutionality. One issue that has been raised by proponents of the use of military commissions is the concern that federal criminal courts would endow accused terrorists with constitutional rights they would not otherwise enjoy. The MCA does not restrict military commissions from exercising jurisdiction within the United States, and the Supreme Court has previously upheld the use of military commissions against "enemy belligerents" tried in the United States under procedural rules that differed from the federal rules. The Supreme Court has not settled the question regarding the extent to which constitutional guarantees apply to aliens detained at Guantanamo, making any difference in rights due to location of the trials difficult to predict. Some view the unpredictability of the Supreme Court's acceptance of the military commission procedures as a factor in favor of using civilian trial courts. The Fifth Amendment to the Constitution provides that "no person shall be ... deprived of life, liberty, or property, without due process of law." Due process includes the opportunity to be heard whenever the government places any of these fundamental liberties at stake. The Constitution contains other explicit rights applicable to various stages of a criminal prosecution. Criminal proceedings provide both the opportunity to contest guilt and to challenge the government's conduct that may have violated the rights of the accused. The system of procedural rules used to conduct a criminal hearing, therefore, serves as a safeguard against violations of constitutional rights that take place outside the courtroom, for example, during arrests and interrogations. The Bill of Rights applies to all citizens of the United States and all aliens within the United States. However, the methods of application of constitutional rights, in particular the remedies available to those whose rights might have been violated, may differ depending on the severity of the punitive measure the government seeks to take and the entity deciding the case. The jurisdiction of various entities to try a person accused of a crime could have a profound effect on the procedural rights of the accused. The type of judicial review available also varies and may be crucial to the outcome. International law also contains some basic guarantees of human rights, including rights of criminal defendants and prisoners. Treaties to which the United States is a party are expressly made a part of the law of the land by the Supremacy Clause of the Constitution and may be codified through implementing legislation, or in some instances, may be directly enforceable by the judiciary. International law is incorporated into U.S. law, but does not take precedence over statute. The law of war, a subset of international law, applies to cases arising from armed conflicts (i.e., war crimes). It remains unclear how the law of war applies to the current hostilities involving non-state terrorists, and the nature of the rights due to accused terrorist/war criminals may depend in part on their status under the Geneva Conventions. The Supreme Court has ruled that Al Qaeda fighters are entitled at least to the baseline protections applicable under Common Article 3 of the Geneva Conventions, which includes protection from the "passing of sentences and the carrying out of executions without previous judgment pronounced by a regularly constituted court, affording all the judicial guarantees which are recognized as indispensable by civilized peoples." The federal judiciary is established by Article III of the Constitution and consists of the Supreme Court and "inferior tribunals" established by Congress. It is a separate and co-equal branch of the federal government, independent of the executive and legislative branches, designed to be insulated from the public passions. Its function is not to make law, but rather to interpret law and decide disputes arising under it. Federal criminal law and procedures are enacted by Congress and codified primarily in title 18 of the U.S. Code. The Supreme Court promulgates procedural rules for criminal trials at the federal district courts, subject to Congress's approval. These rules, namely the Federal Rules of Criminal Procedure (Fed. R. Crim. P.) and the Federal Rules of Evidence (Fed. R. Evid.), incorporate procedural rights that the Constitution and various statutes demand. The charts provided at the end of this report cite relevant rules or court decisions, but make no effort to provide an exhaustive list of authorities. There is historical precedent for using federal courts to try those accused of terrorism or war related offenses, including some that might under some circumstances be characterized as "violations of the law or war." The U.S. Constitution empowers Congress to "define and punish Piracies and Felonies committed on the high Seas, and Offences against the Law of Nations." The First Congress provided for the punishment of persons who committed murder or robbery or the like on the high seas, declaring that each offender was to be "taken and adjudged to be a pirate and felon and being thereof convicted," would be sentenced to death. In 1798, Attorney General Charles Lee advised Secretary of State Timothy Pickering that federal courts were fully competent to try and punish pirates, whether U.S. citizens or aliens. Federal courts exercised jurisdiction in many such cases. More recently, several high-profile prosecutions involving terrorism abroad have resulted in federal convictions. The 1985 hijacking of the Achille Lauro by Palestinian Liberation Organization (PLO) terrorists resulted in the federal conviction of a Lebanese suspect on charges of aircraft piracy and hostage-taking, notwithstanding the defendant's claim to have been merely following military orders. Federal courts also handled prosecutions related to the 1993 bombing of the World Trade Center in New York City, the 2000 bombing of the U.S.S. Cole in the Gulf of Aden, and the 1998 U.S. Embassy bombings in Africa. Federal courts are currently handling several high-profile terrorism cases, including that of Sulaiman Abu Ghaith, a former Al Qaeda spokesman and son-in-law of Osama bin Laden who is on trial in Manhattan on charges of providing material support to Al Qaeda and conspiracy to kill Americans. This and other trials slated to begin soon are seen as providing test cases to demonstrate the efficacy or inadequacy of civilian courts for prosecuting terrorism suspects. In March 2010, the Department of Justice released a list of terrorism trials conducted since 2001, and reported a total of 403 unsealed convictions from September 11, 2001, to March 18, 2010. Around 60% of these convictions were charged under criminal code provisions that are not facially terrorism offenses, including such offenses as fraud, immigration violations, firearms offenses, drug-related offenses, false statements, perjury, obstruction of justice, and general conspiracy charges under 18 U.S.C. Section 371, some of which may not have law-of-war analogs that would permit their trial by military commissions. The remaining 40% are what the Justice Department labeled "Category I Offenses" for the purposes of its report, which covers crimes that are directly related to international terrorism. These crimes include the following: Aircraft Sabotage (18 U.S.C. §32) Animal Enterprise Terrorism (18 U.S.C. §43) Crimes Against Internationally Protected Persons (18 U.S.C. §§112, 878, 1116, l201(a)(4)) Use of Biological, Nuclear, Chemical or Other Weapons of Mass Destruction (18 U.S.C. §§175, 175b, 229, 831, 2332a) Production, Transfer, or Possession of Variola Virus (Smallpox) (18 U.S.C. §175c) Participation in Nuclear and WMD Threats to the United States (18 U.S.C. §832) Conspiracy Within the United States to Murder, Kidnap, or Maim Persons or to Damage Certain Property Overseas (18 U.S.C. §956) Hostage Taking (18 U.S.C. §1203) Terrorist Attacks Against Mass Transportation Systems (18 U.S.C. §1993) Terrorist Acts Abroad Against United States Nationals (18 U.S.C. §2332) Terrorism Transcending National Boundaries (18 U.S.C. §2332b) Bombings of Places of Public Use, Government Facilities, Public Transportation Systems and Infrastructure Facilities (18 U.S.C. §2332f) Missile Systems designed to Destroy Aircraft (18 U.S.C. §2332g) Production, Transfer, or Possession of Radiological Dispersal Devices (18 U.S.C. §2332h) Harboring Terrorists (18 U.S.C. §2339) Providing Material Support to Terrorists (18 U.S.C. §2339A) Providing Material Support to Designated Terrorist Organizations (18 U.S.C. §2339B) Prohibition Against Financing of Terrorism (18 U.S.C. §2339C) Receiving Military-Type Training from a Foreign Terrorist Organization (18 U.S.C. §2339D) Narco-Terrorism (21 U.S.C. §1010A) Sabotage of Nuclear Facilities or Fuel (42 U.S.C. §2284) Aircraft Piracy (49 U.S.C. §46502) Violations of the International Emergency Economic Powers Act (IEEPA, 50 U.S.C. §1705(b)) involving E.O. 12947 (Terrorists Who Threaten to Disrupt the Middle East Peace Process); E.O. 13224 (Blocking Property and Prohibiting Transactions With Persons Who Commit, Threaten to Commit, or Support Terrorism or Global Terrorism List); and E.O. 13129 (Blocking Property and Prohibiting Transactions With the Taliban) The Constitution empowers Congress to declare war and "make rules concerning captures on land and water," to define and punish violations of the "Law of Nations," and to make regulations to govern the armed forces. The power of the President to convene military commissions flows from his authority as Commander in Chief of the Armed Forces and his responsibility to execute the laws of the nation. Under the Articles of War and subsequent statute, the President has at least implicit authority to convene military commissions to try offenses against the law of war. The authority and objectives underlying military courts-martial and military commissions are not coextensive. Rather than serving the internally directed purpose of maintaining discipline and order of the troops, the military commission is externally directed at the enemy as a means of waging successful war by punishing and deterring offenses against the law of war. Military commissions have historically been used in connection with military government in cases of occupation or martial law where ordinary civil government was impaired. Jurisdiction of military commissions is limited to time of war and to trying offenses recognized under the law of war or as designated by statute. While case law suggests that military commissions could try U.S. citizens as enemy belligerents, the Military Commissions Act permits only aliens to be tried. The United States first used military commissions to try enemy belligerents accused of war crimes during the occupation in Mexico in 1847, and made heavy use of them in the Civil War and in the Philippine Insurrection. However, prior to President Bush's Military Order of 2001 establishing military commissions for certain alien terrorism suspects, no military commissions had been convened since the aftermath of World War II. As non-Article III courts, military commissions have not been subject to the same constitutional requirements that are applied in Article III courts. The Military Commissions Act authorizes the Secretary of Defense to establish regulations for military commissions in accordance with its provisions. To date, there have been eight convictions of Guantanamo detainees by military commissions, six of which were procured by plea agreement. A few commission rulings have been appealed. The following charts provide a comparison of the military commissions under the revised Military Commissions Act and standard procedures for federal criminal court under the Federal Rules of Criminal Procedure and the Federal Rules of Evidence. Chart 1 compares the legal authorities for establishing both types of tribunals, the jurisdiction over persons and offenses, and the structures of the tribunals. Chart 2 , which compares procedural safeguards incorporated in the MCA to those applicable in federal criminal cases, follows the same order and format used in CRS Report RL31262, Selected Procedural Safeguards in Federal, Military, and International Courts , Selected Procedural Safeguards in Federal, Military, and International Courts , by [author name scrubbed], in order to facilitate comparison of the those tribunals to safeguards provided in the international military tribunals that tried World War II crimes at Nuremberg and Tokyo, and contemporary ad hoc tribunals set up by the UN Security Council to try crimes associated with hostilities in the former Yugoslavia and Rwanda. For a comparison with previous rules established under President George W. Bush's Military Order, refer to CRS Report RL33688, The Military Commissions Act of 2006: Analysis of Procedural Rules and Comparison with Previous DOD Rules and the Uniform Code of Military Justice . For a comparison of the rules established by the MCA 2006 with those found in the MCA 2009 and to the rules that apply to courts martial under the UCMJ, see CRS Report R41163, The Military Commissions Act of 2009 (MCA 2009): Overview and Legal Issues , by [author name scrubbed].

Summary: The renewal of military commission proceedings against Khalid Sheik Mohammad and four others for their alleged involvement in the 9/11 terrorist attacks has focused renewed attention on the differences between trials in federal court and those conducted by military commission. The decision to try the defendants in military court required a reversal in policy by the Obama Administration, which had publicly announced in November 2009 its plans to transfer the five detainees from the U.S. Naval Station in Guantanamo Bay, Cuba, into the United States to stand trial in the U.S. District Court for the Southern District of New York for criminal offenses related to the 9/11 attacks. The Administration's plans to try these and possibly other Guantanamo detainees in federal court proved controversial, and Congress responded by enacting funding restrictions which effectively barred any non-citizen held at Guantanamo from being transferred into the United States. These restrictions, which have been extended for the duration of FY2014, effectively make military commissions the only viable option for trying detainees held at Guantanamo for the foreseeable future, and have resulted in the Administration choosing to reintroduce charges against Mohammed and his co-defendants before a military commission. While military commission proceedings have been instituted against some suspected enemy belligerents held at Guantanamo, the Obama Administration has opted to bring charges in federal criminal court against terrorist suspects arrested in the United States, as well as some terrorist suspects who were taken into U.S. custody abroad but who were not transferred to Guantanamo. Some who oppose the use of federal criminal courts argue that bringing detainees to the United States for trial poses a security threat and risks disclosing classified information, or could result in the acquittal of persons who are guilty. Others have praised the efficacy and fairness of the federal court system and have argued that it is suitable for trying terrorist suspects and wartime detainees, and have also voiced confidence in the courts' ability to protect national security while achieving justice that will be perceived as such among U.S. allies abroad. Some continue to object to the trials of detainees by military commission, despite the amendments Congress enacted as part of the Military Commissions Act of 2009 (MCA), P.L. 111-84, because they say it demonstrates a less than full commitment to justice or that it casts doubt on the strength of the government's case against those detainees. Others question the continued viability of military commissions in light of the recent appellate court decision invalidating the offense of material support of terrorism as to conduct occurring prior to the 2006 enactment of the MCA (Hamdan v. United States). This report provides a brief summary of legal issues raised by the choice of forum for trying accused terrorists and a chart comparing selected military commissions rules under the Military Commissions Act, as amended, to the corresponding rules that apply in federal court. The chart follows the same order and format used in CRS Report RL31262, Selected Procedural Safeguards in Federal, Military, and International Courts, to facilitate comparison with safeguards provided in international criminal tribunals. For similar charts comparing military commissions as envisioned under the MCA, as originally passed in 2006, to the rules that had been established by the Department of Defense (DOD) for military commissions and to general military courts-martial conducted under the Uniform Code of Military Justice (UCMJ), see CRS Report RL33688, The Military Commissions Act of 2006: Analysis of Procedural Rules and Comparison with Previous DOD Rules and the Uniform Code of Military Justice, by [author name scrubbed].