T his report examines the President's authority to terminate the United States' international obligations under the North American Free Trade Agreement (NAFTA) without further action from Congress. It also examines whether the NAFTA Implementation Act, the primary federal statute that implements the agreement in domestic law, would remain in effect if the President successfully terminated U.S. obligations under the agreement. In analyzing these issues, the report focuses on three related questions: (1) whether, under international law, the President may terminate U.S. international obligations under NAFTA without congressional approval; (2) whether, under domestic law, the President, relying on constitutional or statutory authority, may terminate U.S. international obligations under NAFTA unilaterally; and (3) whether the NAFTA Implementation Act would remain in effect if the President successfully terminated U.S. international obligations under the agreement. NAFTA is an international trade agreement among the United States, Canada, and Mexico that became effective on January 1, 1994. The agreement includes market-opening provisions that remove tariff and nontariff barriers to trade, as well as other rules affecting trade in areas such as agriculture, customs procedures, foreign investment, government procurement, intellectual property protection, and trade in services. The United States approved NAFTA as a congressional-executive agreement by a majority vote of each house of Congress, rather than as a treaty ratified by the President after Senate approval by a two-thirds majority vote. It was not a self-executing agreement; rather, implementing legislation was required to provide domestic legal authorities with the power to enforce and comply with the agreement's provisions. Congress approved and implemented NAFTA in domestic law in the NAFTA Implementation Act. Although many U.S. obligations under NAFTA were already implemented in domestic law prior to Congress's enactment of the NAFTA Implementation Act, Congress delegated rulemaking authority to the President and various federal agencies in the Act so that they could further implement NAFTA in domestic law by promulgating executive orders, proclamations, or regulations. The NAFTA implementing legislation contemplates certain limited changes to certain provisions of NAFTA (e.g., certain rules of origin) in accordance with NAFTA's rules for minor amendments to the text of the agreement and limited congressional delegations of authority to the President to implement such changes in U.S. law. On May 18, 2017, U.S. Trade Representative (USTR) Ambassador Robert Lighthizer notified Congress that the Administration intended to renegotiate NAFTA. More than a year later, following the conclusion of the negotiations, President Trump signed a proposed replacement for NAFTA, the United States-Mexico-Canada Free Trade Agreement (USMCA), along with his counterparts from Canada and Mexico. The new agreement addressed a variety of issues, including changes to rules of origin for automotive trade; intellectual property rights protections; digital trade; limitations on the scope of investor-state dispute settlement (ISDS) provisions; and certain provisions on agricultural trade. President Trump has at times suggested that he will withdraw the United States from NAFTA unilaterally if Congress does not approve the USMCA. International law does not itself prohibit the President from unilaterally terminating the United States' obligations under NAFTA. NAFTA is a legally binding agreement under international law. In other words, NAFTA is a "treaty" under international law, a term that has a more expansive meaning than the same term when used in U.S. domestic practice. In this regard, it is important to distinguish "treaty" in the context of international law, in which "treaty" and "international agreement" are synonymous terms for all binding agreements, and "treaty" in the context of domestic American law, in which "treaty" may more narrowly refer to a particular subcategory of binding international agreements that receive the Senate's advice and consent. Part V of the Vienna Convention on the Law of Treaties (Vienna Convention), which the United States has not ratified but considers to reflect, in many aspects, customary international law, provides rules for withdrawal of a party from a binding international agreement. Article 54 of the Vienna Convention provides that "termination of a treaty or the withdrawal of a party may take place . . . in conformity with the provisions of the treaty . . . ." Article 2205 of NAFTA, which Congress approved in the NAFTA Implementation Act, provides that a "Party may withdraw from this Agreement six months after it provides written notice of withdrawal to the other Parties. If a Party withdraws, the Agreement shall remain in force for the remaining Parties." NAFTA does not address whether, in the context of the United States' withdrawal from the agreement, the term "Party" includes both the President and Congress acting together to accomplish withdrawal. In addition, neither the other provisions of the agreement, the context in which they appear, nor the subsequent practice of the NAFTA parties sheds light on the issue. In the absence of language to the contrary in NAFTA Article 2205, the Vienna Convention applies. Article 67 of the Vienna Convention provides that: Any act of declaring invalid, terminating, withdrawing from or suspending the operation of a treaty pursuant to the provisions of the treaty . . . shall be carried out through an instrument communicated to the other parties. If the instrument is not signed by the Head of State, Head of Government or Minister for Foreign Affairs, the representative of the State communicating it may be called upon to produce full powers [i.e., a document showing that the representative has authority to terminate the agreement on behalf of the state]. It thus appears that if the President (i.e., the "head of state" for the United States) communicated a notice of withdrawal from NAFTA to Canada and Mexico, and such notice became effective at least six months later, it would terminate the United States' obligations under the agreement as a matter of international law. The withdrawal process under international law, however, may not account for the unique statutory, constitutional, and separation-of-powers principles related to withdrawal under U.S. domestic law, as discussed below. If the President sought to terminate U.S. international obligations under NAFTA, an injured business or other party with standing to bring a lawsuit might seek an injunction from a U.S. federal court directing the executive branch to refrain from issuing a notice terminating U.S. obligations under NAFTA or a declaration from the court that such issuance is unlawful. It is difficult to predict how a court might resolve such a challenge, as U.S. courts have uniformly avoided answering whether the U.S. Constitution authorizes the President to terminate an international pact without express congressional approval. Instead, courts have left the executive and legislative branches to resolve disagreements over the termination power through the political process. While no court has considered a case involving a trade agreement approved as a congressional-executive agreement under Trade Promotion Authority (TPA) procedures, there is a significant possibility that a court would dismiss such a case for lack of jurisdiction. Congress could signal that it disputes the Executive's termination of U.S. NAFTA obligations to a court by enacting a law or resolution with a veto-proof majority opposing or purporting to block such action. If Congress passed such an act or resolution and the Executive still terminated NAFTA in direct derogation of that act or resolution, the legal paradigm governing the separation-of-powers analysis might shift. To resolve certain separation-of-powers conflicts, the Supreme Court typically applies the approach set forth in Justice Jackson's concurring opinion in Youngstown Sheet & Tube Co. v. Sawyer , which states that the President's constitutional powers often "are not fixed but fluctuate, depending on their disjunction or conjunction with those of Congress." Justice Jackson's opinion sets forth a tripartite framework for evaluating the constitutional powers of the President. The President's authority is (1) at a maximum when acting pursuant to authorization by Congress; (2) in a "zone of twilight" when Congress and the President "may have concurrent authority, or in which its distribution is uncertain," and Congress has not spoken on an issue; and (3) at its "lowest ebb" when taking measures incompatible with the will of Congress. Although Congress has not enacted a law or resolution prohibiting the President from terminating NAFTA unilaterally, such action could place the President's authority at the "lowest ebb." In that scenario, the President may act in contravention of the will of Congress only in matters involving exclusive presidential prerogatives that are "at once so conclusive and preclusive" that they "disabl[e] the Congress from acting upon the subject." Members of the executive branch have suggested that treaty termination is part of the President's plenary powers, but one could plausibly advance the counterargument that the legislative branch plays a shared role in the termination process, especially in matters that implicate Congress's enumerated powers, such as international trade. Assuming that a federal court found a case challenging the President's termination of NAFTA to be justiciable, it would likely evaluate the President's authority to take such action. Because Congress has not enacted a resolution or legislation disapproving of unilateral NAFTA termination, in order to terminate NAFTA without further congressional action, either (1) the President must possess plenary constitutional authority to terminate U.S. international obligations under NAFTA, or (2) Congress must have authorized the President to take such action through legislation. Although the Constitution establishes a procedure whereby the Executive has the power to make treaties with the advice and consent of the Senate, it is silent as to how the United States may withdraw from treaties or congressional-executive agreements. Scholars have also noted that the framers of the Constitution never directly addressed the power to terminate treaties (or congressional-executive agreements) in the Federalist Papers , the Constitutional Convention debates, or the debates of the state ratifying conventions. In the absence of guidance from the text or original meaning of the Constitution, a court considering whether the President has the constitutional authority to terminate U.S. international obligations under NAFTA without congressional approval would likely turn to other methods of constitutional interpretation. As discussed below, applying relevant methods of interpretation does not provide a clear answer as to whether the President possesses plenary constitutional authority to terminate U.S. obligations under NAFTA. One method of constitutional interpretation, known as structuralism, draws inferences from the design of the Constitution, including the relationships among the three branches of the federal government (commonly called separation of powers). In this vein, Article I, Section 8 of the Constitution specifically gives Congress the authority to impose duties on imports of products from other countries and to "regulate Commerce with foreign Nations." By contrast, although the President may possess constitutional authority to negotiate trade agreements and communicate a notice of withdrawal from an agreement to trading partners, Article II gives the President no specific power over international commerce or trade. The manner in which the Constitution apportions power over international commerce, granting such power specifically to Congress, suggests that the President may simply lack authority to terminate U.S. international obligations under NAFTA, which addresses commercial matters, without further congressional action. The Supreme Court, however, has interpreted Article II of the Constitution as granting the President the "vast share of responsibility" for conducting foreign relations. This authority includes, but also extends beyond, specific Article II powers to appoint ambassadors with advice and consent of the Senate; submit treaties to the Senate; ratify treaties; and act as the Commander in Chief of the Armed Forces. Courts and scholars generally accept that such authority includes the exclusive authority to negotiate treaties and international agreements and make official communications with foreign states. Because terminating the United States' NAFTA obligations implicates foreign relations and, more specifically, communication of a notice of withdrawal to foreign sovereigns (i.e., Canada and Mexico), one could argue that the design of the Constitution provides the President with independent power to terminate NAFTA unilaterally. Nonetheless, the President's preeminent role in communicating with foreign powers does not necessarily imply that he has authority to terminate a trade agreement without congressional consent. Long-established historical practices of the political branches may also be relevant to whether the President can terminate NAFTA unilaterally. In some cases, the United States has withdrawn from international legal agreements pursuant to the joint action of the political branches. However, beginning at the turn of the 20th century, the President has sometimes withdrawn unilaterally from an international agreement without the consent of Congress. Thus, general historical practice involving the termination of international agreements has been inconsistent, and therefore it may not be particularly helpful in resolving questions about the President's power to terminate trade agreements unilaterally. Defining the relevant historical practice more narrowly provides little guidance, as well. Historical experience with the suspension of modern free trade agreements (FTAs)—those subsequently approved and implemented in domestic law as congressional-executive agreements by a majority vote in both houses of Congress under Trade Promotion Authority (TPA) procedures—is limited. In fact, no U.S. FTA approved as a congressional-executive agreement under these procedures has been terminated. In the single instance involving suspension rather than termination of an FTA, Congress amended the act implementing the U.S.-Canada Free Trade Agreement preceding NAFTA to suspend certain provisions in the act while allowing others to continue to operate. Although this historical practice concerns suspension of an FTA rather than termination, a court could interpret it to suggest that Congress may have a role in terminating U.S. international obligations under NAFTA. However, because it is a single instance and involves suspension rather than termination of an agreement, a court could also find it to provide little guidance on the President's authority in this context. The practical consequences of a court concluding that the President possesses the power to terminate a trade agreement unilaterally may also be relevant. Generally, a pragmatic approach to constitutional interpretation weighs the future costs and benefits of an interpretation to society or the political branches, selecting the interpretation that may lead to the perceived best outcome. However, it is difficult to predict which set of pragmatic arguments a court would find most persuasive. On the one hand, one could argue that the President should possess an exclusive power of unilateral termination because (1) the nation must have a "single policy" regarding which international trade agreements remain in effect, and (2) additional pronouncements from Congress on the issue could result in confusion for the United States and its trading partners. One might also arguably justify a unilateral termination power on the grounds that the United States needs a means to make decisive, quick, and clear decisions on withdrawal from NAFTA or other FTAs, particularly when another party has breached the agreement, and that it would make it easier for the President to threaten NAFTA partners with U.S. withdrawal from the agreement as a means of leverage to obtain concessions from them during renegotiation of the agreement. On the other hand, one could instead argue that a unilateral termination power would improperly allow a single actor (i.e., the President) to eliminate an international commercial agreement. In addition, the President's use of such a power could be viewed to undermine the United States' ability to make convincing international commitments in the realm of trade as well as other areas. Notwithstanding whether the President has plenary constitutional authority to terminate NAFTA, the President could terminate NAFTA without first seeking congressional approval if Congress has already given the Executive such authorization either expressly or by implication. It is unclear whether a court would find that Congress has implicitly approved of unilateral presidential termination of NAFTA obligations. Congress has enacted a detailed statutory framework for the negotiation, legislative consideration, and implementation of free trade agreements under Trade Promotion Authority (TPA) procedures. During the past few decades, Congress and the President have used this legal framework to conclude and implement 14 free trade agreements with 20 countries, including NAFTA. Given this extensive framework for legislative approval and implementation of trade agreements, a court might find it unlikely that Congress implicitly authorized the President to withdraw from NAFTA without further congressional action. On the other hand, the fact that Congress enacted a comprehensive statutory framework for entering into trade agreements, but not withdrawing from them, may indicate that Congress was not as concerned with the President's termination of U.S. obligations under the agreements. Nonetheless, some commentators have argued that Congress has specifically authorized the President to terminate U.S. international obligations under NAFTA. In particular, these commentators have pointed to Sections 125 and 301 of the Trade Act of 1974, an act that, among other things, sets up the procedure for Congress's consideration of trade agreement implementing legislation, as potentially providing such authority. The following subsections of this report therefore analyze whether Sections 125 and 301 grant the President this termination authority. Some commentators have argued that Section 125(a) of the Trade Act of 1974 authorizes the President to terminate U.S. NAFTA commitments. Congress specifically made this subsection applicable to NAFTA in the Omnibus Trade and Competitiveness Act of 1988, the Trade Promotion Authority (TPA) legislation for NAFTA. Section 125(a), titled "Termination and Withdrawal Authority," which specifically addresses withdrawal from FTAs, provides the following: (a) Grant of authority for termination or withdrawal at end of period specified in agreement Every trade agreement entered into under [the Trade Act of 1974] shall be subject to termination, in whole or in part, or withdrawal, upon due notice, at the end of a period specified in the agreement. Such period shall be not more than 3 years from the date on which the agreement becomes effective. If the agreement is not terminated or withdrawn from at the end of the period so specified, it shall be subject to termination or withdrawal thereafter upon not more than 6 months' notice. If the President were to invoke Section 125(a) as authority for terminating U.S. international obligations under NAFTA, his actions might be challenged in federal court as exceeding the statutory authority delegated to him. Because no court has yet interpreted Section 125(a), the scope of the President's power under this provision would be an issue of first impression. In deciding whether Section 125(a) authorizes the President to terminate U.S. obligations under NAFTA, the court might consider several principles of statutory interpretation. First, a court would likely consider the ordinary meaning of the text. In this vein, the title of subsection (a) may provide some guidance. The title "Grant of authority for termination or withdrawal at end of period specified in agreement" may suggest that Congress's purpose in enacting Section 125(a) was to "grant" the President the authority to terminate the agreement in accordance with the withdrawal provision in NAFTA Article 2205 without the need for further legislation. However, the Supreme Court has stated that statutory headings and titles "are not meant to take the place of the detailed provisions of the text" and that the title of an act "cannot enlarge or confer powers." Although the title of subsection (a) may provide limited interpretive aid, it does not specify which political actor has withdrawal authority. Thus, it is unlikely that a court would view it as conferring authority on the President to terminate U.S. obligations under NAFTA. Turning to the text of Section 125(a), the provision states that agreements like NAFTA "shall be subject to termination." The relevant dictionary definition of "subject" is "contingent on or under the influence of some later action." To say that NAFTA is "subject to" termination means that it is capable of later being terminated but says nothing about which political actor(s) must terminate the agreement. This reading is supported by the canon of statutory construction that "Congress . . . does not alter the fundamental details of a regulatory scheme in vague terms or ancillary provisions—it does not . . . hide elephants in mouseholes." It seems unlikely that Congress would have "hidden" a delegation of authority to the President to terminate NAFTA in a vaguely worded provision. Rather, the ordinary meaning of Section 125(a) appears to require only that the text of the NAFTA agreement contain a provision allowing for its termination. Legislative history materials appear to confirm this reading of Section 125(a). These materials suggest that Section 125(a)'s purpose was to ensure that trade agreements entered into by the President contained language providing for termination or withdrawal at the end of a certain time period. This reading is suggested by the House Committee on Ways and Means report on a predecessor to Section 125, Section 2(b) of the 1934 Reciprocal Trade Agreements Act. Congress enacted that law to authorize the President to negotiate reciprocal agreements reducing barriers to international trade during the Great Depression in order to stimulate the domestic economy. The House committee report stated the following: The final provision of the bill under consideration deals with the amount of time during which a foreign trade agreement with another country may run. The provision is that such agreement must be terminable at the end of not more than 3 years. If it is not terminated at that time it must thereafter be terminable at any time upon not more than 6 month[s'] notice. The committee reports thus suggest that Section 125(a)'s purpose was to ensure that the trade agreements that the President entered into would be subject to termination or terminable . Under this reading, Section 125(a) does not appear to delegate authority to the President to terminate those agreements unilaterally by delivering notice of withdrawal to trading partners. One scholar has argued that Section 301 of the Trade Act of 1974 authorizes the President to terminate U.S. obligations under NAFTA. Section 301 provides that the Office of the United States Trade Representative (USTR), a federal agency within the Executive Office of the President, must take certain specified trade actions "subject to the specific direction, if any, of the President regarding any such action" when it finds, after conducting an investigation and following other procedures, that: (A) the rights of the United States under any trade agreement are being denied; or (B) an act, policy, or practice of a foreign country—(i) violates, or is inconsistent with, the provisions of, or otherwise denies benefits to the United States under, any trade agreement, or (ii) is unjustifiable and burdens or restricts United States commerce. Section 301 also provides the USTR with discretion to take "all appropriate and feasible" trade actions specifically authorized under subsection (c) when it finds that "an act, policy, or practice of a foreign country is unreasonable or discriminatory and burdens or restricts United States commerce, and . . . action by the United States is appropriate." Section 301(c) provides a list of actions that the USTR may or must take in response to the unfair foreign trade practices. As relevant here, that list authorizes USTR to: (A) suspend, withdraw, or prevent the application of, benefits of trade agreement concessions to carry out a trade agreement with the foreign country [that is the subject of the Section 301 investigation]; (B) impose duties or other import restrictions on the goods of, and, notwithstanding any other provision of law, fees or restrictions on the services of, such foreign country for such time as the Trade Representative determines appropriate . . . Notably, the list of actions in Section 301(c) does not explicitly include authorization for the Executive to deliver a notice of withdrawal from a trade agreement to U.S. trading partners and thereby terminate U.S. obligations under the agreement. Rather, as discussed further below, the legislative history of this provision, as recounted in committee reports, indicates that Congress merely intended the provision to provide the President broad authority to take action against unfair foreign trade practices by imposing various barriers to trade under domestic law, including by suspending or terminating individual trade concessions. The text and legislative history do not appear to suggest that Section 301(c) more broadly authorizes the USTR to terminate a trade agreement. However, as discussed below, the Executive might exercise the authority in Section 301 to establish significant barriers to trade with Canada and Mexico. Accordingly, if the USTR were to interpret Section 301(c) as authorizing it to terminate a trade agreement, it would appear that its actions would fall outside of the statutory authority delegated to the agency. It should be noted that courts reviewing specific USTR actions under Section 301 have in the past accorded "substantial deference to decisions of the Trade Representative implicating the discretionary authority of the President in matters of foreign relations," including the USTR's selection of a remedy following a Section 301 investigation. But the U.S. Court of Appeals for the Federal Circuit, which reviews the USTR's actions under Section 301, has held that, under the Administrative Procedure Act, "[t]he judiciary is the final authority on issues of statutory construction and must reject administrative constructions which are contrary to clear congressional intent." Furthermore, a court may hold agency action unlawful when there has been "a clear misconstruction of the governing statute" or "action outside delegated authority." Because the text and legislative history of Section 301 indicate that Congress merely intended the provision to furnish the Executive with broad authority to take action against unfair foreign trade practices by imposing various barriers to trade under domestic law, it seems unlikely that a court would accord deference to a USTR interpretation that Section 301 authorizes the President to deliver notice of termination to Canada or Mexico. Although neither Section 125 nor Section 301 of the Trade Act of 1974 appears to authorize the Executive to terminate U.S. international obligations under NAFTA, these statutory provisions appear to grant broad authority to the executive branch to impose barriers to trade on goods and services from Canada and Mexico under domestic law. For example, the text and legislative history of Section 125(b)-(f) suggest that Congress intended to provide the President with broad authority to terminate various presidential proclamations implementing a trade agreement in domestic law (e.g., proclamations implementing tariff reductions) and to impose trade barriers in order to, for example, respond to a breach of the agreement by another party. And the text and legislative history of Section 301, as recounted in committee reports, indicate that the provision was intended to provide the Executive with broad authority to effect the temporary suspension or withdrawal of individual trade concessions accorded by the United States to the goods and services of trading partners while a trade agreement remained in effect. Although such provisions appear to furnish the executive branch with broad authority to suspend or terminate individual trade concessions, the Executive's actions under these provisions could be subject to challenge before international and domestic tribunals. For example, the Executive's imposition of trade barriers pursuant to such authorities may place the United States in breach of its obligations under other international agreements, such as the World Trade Organization (WTO) agreements. If a dispute proceeded to a WTO panel, and the panel rendered an adverse decision against the United States, the United States would be expected to remove the offending measure, generally within a reasonable period of time, or face the possibility of paying compensation to the complaining member or being subject to sanctions. Such sanctions might include the complaining member imposing higher duties on imports of selected products from the United States. However, a WTO Member could begin to impose its own duties on selected U.S. exports without awaiting the outcome of a dispute settlement proceeding. In addition, a domestic court might consider whether, in exercising authority under Section 125, the President acted within the scope of his delegated powers as defined by the terms of the statute, or whether the President's actions were proportional to the circumstances cited to justify them. As a further example, a federal court could review USTR's Section 301 actions under the Administrative Procedure Act to determine whether they are "arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law." A reviewing court might consider, for example, whether the USTR's Section 301 actions involved "a clear misconstruction of the governing statute," "a significant procedural violation," or "action outside delegated authority." The NAFTA Implementation Act, the primary federal statute that implements NAFTA in domestic law, would likely remain in effect if the President successfully terminated the United States' international obligations under NAFTA unilaterally. Under Supreme Court precedent, the repealing of statutes generally must conform to the same bicameral and presentment process set forth in Article I that is used to enact new legislation. For example, in Clinton v. City of New York , the Supreme Court struck down the Line Item Veto Act (LIVA), a law that authorized the President, within five days of signing a bill into law, to make partial cancellation of certain tax and spending provisions in the law if the President determined certain criteria were met. The Court held that the LIVA violated the bicameralism and presentment requirements of the Constitution because the President could effectively repeal acts of Congress without going through the regular legislative process involving House and Senate passage of legislation and presentment of it to the President for his signature or veto. Nonetheless, the Court has recognized Congress's authority to enact contingent legislation that provides for the alteration of a law's effect based on a condition that arises after the law is enacted. It should be noted that Sections 109(b) and 415 of the NAFTA Implementation Act contain language that could be read to effect the repeal of certain provisions of the NAFTA Implementation Act under specific circumstances. Specifically, section 109(b) states the following: (b) TERMINATION OF NAFTA STATUS—During any period in which a country ceases to be a NAFTA country, sections 101 through 106 shall cease to have effect with respect to such country. Section 415(a) provides similar language with respect to certain provisions addressing dispute settlement in antidumping and countervailing duty cases in Title IV of the NAFTA Implementation Act: IN GENERAL—Except as provided in subsection (b)[, which contains transitional provisions], on the date on which a country ceases to be a NAFTA country, the provisions of this title (other than this section) and the amendments made by this title shall cease to have effect with respect to that country. The NAFTA Implementation Act defines "NAFTA country" as those countries (i.e., Canada and Mexico) (1) to which the agreement is in force and (2) to which the United States "applies the Agreement." The text and legislative history of Sections 109(b) and 415 of the NAFTA Implementation Act indicate that Congress intended these sections to trigger automatic termination of certain provisions of the Act with respect to Canada or Mexico when either country withdrew from NAFTA but the United States remained a party. However, it is unclear what language in either of these provisions would afford the President the authority to terminate the agreement without such conduct by Canada or Mexico. Moreover, interpreting Sections 109(b) and 415 to provide for the automatic termination of certain provisions in the NAFTA Implementation Act when the President unilaterally terminates U.S. NAFTA obligations under international law would appear to violate a key canon of statutory construction that holds that if one plausible reading of a statute would raise questions about the statute's constitutionality, a court should look for another, "fairly possible" reading that would avoid the constitutional issue. Interpreting Sections 109(b) and 415 to authorize the President to terminate portions of the NAFTA Implementation Act by withdrawing the United States from NAFTA would raise the question of whether Congress's delegation of such authority to the President violates separation-of-powers principles by contravening the Presentment Clause of the Constitution, which, as noted above, requires that legislation be passed by Congress and presented to the President for his signature or veto in order to become law. Accordingly, a more likely reading of Sections 109(b) and 415 would likely be that certain provisions of the NAFTA Implementation Act cease to have effect with respect to Canada or Mexico if either country withdraws from NAFTA but the United States remains a party. Therefore, absent further congressional action, the United States' withdrawal from NAFTA alone appears unlikely to trigger Sections 109(b) and 415 or render the NAFTA Implementation Act ineffective. Notably, even if the NAFTA Implementation Act remains in effect, other provisions of federal law (e.g., Section 301 of the Trade Act of 1974) may grant the President or a federal agency authority to restrict trade with Canada or Mexico. As noted, such actions would likely be subject to judicial review on various grounds.

Summary: NAFTA is an international trade agreement among the United States, Canada, and Mexico that became effective on January 1, 1994. The agreement includes market-opening provisions that remove tariff and nontariff barriers to trade, as well as other rules affecting trade in areas such as agriculture, customs procedures, foreign investment, government procurement, intellectual property protection, and trade in services. Congress approved and implemented NAFTA in domestic law in the NAFTA Implementation Act (P.L. 103-182, 107 Stat. 2057). On May 18, 2017, U.S. Trade Representative Ambassador Robert Lighthizer notified Congress that the Administration intended to renegotiate NAFTA. More than a year later, following the conclusion of the negotiations, President Trump signed a proposed replacement for NAFTA, the United States-Mexico-Canada Free Trade Agreement (USMCA), along with his counterparts from Canada and Mexico. President Trump has at times suggested that he will withdraw the United States from NAFTA unilaterally if Congress does not approve the USMCA. This report examines the President's authority to terminate the United States' international obligations under NAFTA without further action from Congress. It also examines whether the NAFTA Implementation Act, the primary federal statute that implements the agreement in domestic law, would remain in effect if the President successfully terminated U.S. obligations under the agreement. In analyzing these issues, the report focuses on three related questions: (1) whether, under international law, the President may terminate U.S. international obligations under NAFTA without congressional approval; (2) whether, under domestic law, the President, relying on constitutional or statutory authority, may terminate U.S. international obligations under NAFTA unilaterally; and (3) whether the NAFTA Implementation Act would remain in effect if the President successfully terminated U.S. international obligations under the agreement. With regard to the first question, under international law, the President appears to be able to terminate the United States' international obligations under NAFTA without congressional approval by delivering six months' notice of withdrawal to Canada and Mexico, provided such notice later becomes effective (e.g., assuming that a court does not enjoin the Executive from issuing the notice or declare such issuance unlawful). The answer to the second question is less clear, however, and would require a reviewing court to confront several complicated issues of first impression, including the scope of the President's constitutional authority and statutory authority to terminate an international agreement. Justiciability questions may prevent a court from definitively answering the constitutional questions, leaving the resolution of the President's constitutional authority to the political process. With regard to the statutory question, while legal commentators have raised various arguments with respect to the President's domestic legal authority to terminate U.S. NAFTA international obligations unilaterally, it does not appear that any statute expressly affords the President with the authority to terminate NAFTA on his own. It is unclear whether Congress's enactment of an extensive legal framework providing for legislative consideration, approval, and implementation of trade agreements indicates that Congress did not intend to authorize the President implicitly to withdraw from NAFTA without further congressional action. Nonetheless, as explained below, provisions of federal law such as Sections 125 and 301 of the Trade Act of 1974 may provide the Executive with broad authority to suspend individual trade concessions granted to NAFTA countries and thereby establish barriers to trade with Canada and Mexico. At the same time, the Executive's use of such authority would, however, likely be subject to review on various grounds by domestic or international tribunals. Finally, whether the NAFTA Implementation Act would remain in effect after termination of U.S. obligations under NAFTA would be informed by Supreme Court precedent generally requiring the repeal of statutes to conform to the same bicameral process set forth in Article I of the Constitution that is used to enact new legislation. Accordingly, as an initial matter, it would appear that the President lacks authority to terminate the domestic effect of the NAFTA Implementation Act without going through the full legislative process for repeal. Thus, the Act appears to remain in effect unless Congress has, consistent with the Constitution, delegated to the President authority to terminate its provisions or made such provisions "self-terminating."