The primary legislation governing U.S. relations with the ICC is the American Servicemembers' Protection Act (ASPA), which was enacted on August 2, 2002 with bipartisan support. ⁴¹ The focus of this legislation, as the name and the congressional findings make clear, was the protection of U.S. servicemembers from the exercise of jurisdiction by the Court. ⁴² Key provisions prohibit any extradition from the United States to the ICC or support for any transfer of a U.S. citizen or permanent resident to the ICC; prohibit any funding to assist in the investigation, arrest, detention, extradition, or prosecution of any U.S. citizens or permanent residents by the ICC; and authorize the President to use ”all means necessary"—a phrase that is understood to include military force—to bring about the release of U.S. persons who might be detained by or on behalf of the Court. ⁴³ Other provisions in ASPA impose restrictions on the United States' ability to support or cooperate with the ICC—including the provision of financial support, services, or law enforcement cooperation; the transfer of property or other material support; intelligence sharing; the training or detail of personnel; the arrest or detention of individuals; the ability of U.S. courts and state and local governmental entities to respond to ICC requests for cooperation; and ICC investigative activity in the United States (See Text Box - ASPA - Key Restrictions).

These restrictions are subject, however, to a significant exception introduced by then-Senator Christopher Dodd (D-CT), whose father was a prosecutor at Nuremberg. Specifically, under the plain language of the Dodd Amendment, nothing in ASPA prohibits the United States from assisting international efforts to bring to justice foreign nationals accused of genocide, crimes against humanity, and war crimes, including before the ICC. ⁴⁴

The Dodd Amendment is capacious, but there are situations that it does not cover. For example, it does not apply to any assistance to prosecutions of U.S. nationals, to efforts to prosecute any defendant for the crime of aggression, and—at least arguably—to general institutional support to the ICC that is not sufficiently connected to efforts to bring particular individuals to justice (e.g., general training or capacity building). That said, the identification in the text of the amendment of individuals who had not yet been indicted by any court ⁴⁵ and the inclusion of categories of perpetrators (such as “other members of Al Queda [sic]” and “leaders of Islamic Jihad”) at least suggest that a criminal case need not have been commenced in order for the Dodd Amendment to apply, and that it may include supporting efforts to investigate the responsibility of a group whose members are understood to be exclusively or predominantly not American with a view “to bring[ing them] to justice.” Furthermore, there are questions whether this exception should be interpreted to overcome restrictions on the ability of the ICC to conduct investigative activity in the United States in support of cases that would otherwise fall within the Dodd Amendment. Nevertheless, the Dodd Amendment creates significant flexibility for the United States to provide a range of forms of support for investigations or prosecutions for atrocity crimes of foreign nationals if it is so inclined. ⁴⁶

Changes made over time to ASPA highlight the United States' evolving relationship with the ICC and the multiple interests at play. For example, as originally enacted, ASPA contained restrictions on the provision of military assistance to states parties that did not enter into agreements pursuant to Article 98 of the Rome Statute to prevent the surrender of U.S. persons to the Court. ⁴⁷ At least one hundred states ratified such agreements between late 2002 and 2007. ⁴⁸ However, a number of states (including all NATO allies other than Turkey) refused to do so and the EU issued “Guiding Principles” that stated that “[e]ntering into US agreements as presently drafted would be inconsistent with ICC States Parties' obligations." ⁴⁹ Over time, however, U.S. officials came to see these restrictions on military assistance as counter-productive, with the then-Commander of U.S. Southern Command, General Bantz Craddock, testifying that “loss of engagement prevents the development of long-term relationships with future [Latin American] military and civilian leaders." ⁵⁰ In addition, there were concerns that the restrictions may enable foreign adversaries, including China, to step into the vacuum left by the United States and to build credibility and cooperative relationships with countries with which the United States traditionally had close relationships. ⁵¹ In May 2006, Secretary of State Condoleezza Rice memorably described prioritizing opposition to the ICC over other U.S. interests as amounting to “sort of the same as shooting ourselves in the foot." ⁵² As these concerns came to the fore, Congress repealed the restrictions and the Bush Administration discontinued its efforts to secure additional such Article 98 agreements. ⁵³

In addition to ASPA, an earlier statute has been interpreted as providing certain limitations on U.S. engagement with the Court that are not subject to the Dodd Amendment. ⁵⁴ Section 705(b) of the FY2000–01 Foreign Relations Authorizations Act (FRAA) restricts any funding “for use by, or support of, the International Criminal Court” unless and until the United States ratifies the Rome Statute (See Text Box -FRAA Restriction on Funding the ICC, § 705(b)). More recently, Congress has included a provision in annual appropriations legislation that prohibits funds under the State Department Appropriations Act from being made available to the ICC, but which contains a proviso allowing funds to be used to support certain technical assistance training, assistance to victims and witness protection, law enforcement, and other activities. ⁵⁵