T he scope of the executive's discretion in implementing federal immigration law is a topic of perennial interest to Members and committees of Congress. Most recently, questions have been raised as to whether particular actions announced by the Obama Administration in November 2014 are within the executive's authority. However, similar questions were raised in the past about other executive actions including, but not limited to (1) suspending enforcement of certain provisions of the Immigration and Nationality Act (INA) in areas affected by natural disasters; (2) granting deferred enforced departure, extended voluntary departure, or other relief from removal to certain aliens who entered or remained in the United States in violation of the INA; and (3) "paroling," or permitting the entry of, certain aliens into the United States who were not admissible under current law. The debate over whether particular actions are within the executive's authority—acting on its own and without the enactment of additional legislation by Congress—ultimately reflects the respective roles that the executive and legislative branches play in the nation's constitutional system of government. Article I of the Constitution expressly grants the power to legislate to Congress, and Congress has exercised this power as to immigration, in part, by enacting the INA. The INA provides a comprehensive set of rules governing the admission of foreign nationals into the United States and the conditions of such aliens' continued presence in the country, including their eligibility to obtain employment and public benefits, change or adjust their immigration status, and become U.S. citizens. In addition, the INA establishes various mechanisms for enforcing these rules, including by prescribing the removal of aliens found to have entered the United States without permission, or to have violated the terms governing their authorized admission into the country. It also establishes criminal penalties for certain immigration violations. On the other hand, the INA expressly or impliedly confers some discretionary authority on the executive branch in matters of immigration enforcement. For example, the INA authorizes immigration officials to grant certain types of benefits or relief to qualifying aliens who lack lawful immigration status. Moreover, the INA permits immigration officials to waive certain statutory restrictions that might otherwise render an alien ineligible to receive particular immigration benefits. The exercise of these discretionary authorities may enable some unlawfully present aliens to remain in the United States—through asylum, temporary protected status, cancellation of removal, or some other means—rather than being removed. In other cases, however, aliens who have entered or have stayed in the United States in violation of INA requirements may be permitted to remain in the country and, in some cases, legalize their status, not as the result of the exercise of expressly delegated authority, but as a result of the executive branch's independent discretion in enforcing the law. Article II of the Constitution specifically tasks the executive to "take Care that the Laws be faithfully executed," and the executive branch has historically been seen as having some discretion in determining when, against whom, how, and even whether to prosecute apparent violations of the law. For example, immigration officials m ay opt to give a lower priority to the removal of certain categories of unlawfully present aliens because the removal of other categories (e.g., those convicted of serious crimes) has been deemed a higher priority in light of resource constraints and other considerations. Congressional enactments could, however, be seen as limiting the executive's discretion not to take particular actions (e.g., by mandating that certain aliens be detained pending removal proceedings). The express adoption of an executive policy that is "in effect an abdication of ... statutory duty" could also be found to be impermissible, but it might be difficult for a court to assess whether an alleged failure to enforce the law constitutes an abdication. The executive branch's discretion to interpret applicable statutes when Congress has not spoken to the precise question at issue may also afford immigration officials some flexibility in determining how INA requirements apply to a particular alien or category of aliens. This discretion may be relevant in determining how particular statutory grants of discretionary authority are to be applied (e.g., what constitutes "exceptional and extremely unusual hardship" for purposes of cancellation of removal, or "extreme hardship" for purposes of certain waivers of inadmissibility). It can also play a role in determining whether and how particular statutes are seen to circumscribe the executive's enforcement discretion. That is, where a statute is silent or ambiguous as to the circumstances of its enforcement in particular cases, the executive may have some discretion in determining its application. This report provides an overview of the three broad types of discretion that the executive can be seen to have as to immigration. Namely (1) express delegations of discretionary authority; (2) discretion in enforcement (commonly known as prosecutorial or enforcement discretion); and (3) discretion in interpreting and applying statutes. In so doing, it provides notable examples of each broad type of discretion, as well as potential constraints upon the exercise of particular types of discretion. Separate reports discuss prosecutorial discretion in immigration enforcement and the Take Care Clause—which some have suggested constrains the executive's exercise of discretion —in greater detail. See generally archived CRS Report R42924, Prosecutorial Discretion in Immigration Enforcement: Legal Issues , by [author name scrubbed] and [author name scrubbed]; CRS Report R43708, The Take Care Clause and Executive Discretion in the Enforcement of Law , by [author name scrubbed]. In several instances, the INA expressly grants immigration officials some degree of discretion over aliens' eligibility for particular immigration benefits or relief, including adjustment to legal immigration status or authorization to work in the United States. These statutory delegations sometimes provide immigration officials with broad discretion to determine whether and when aliens may be eligible for particular immigration benefits. In other instances, such delegations may permit immigration officials to waive the application of a statutory requirement that would bar otherwise qualifying aliens from obtaining particular immigration benefits or relief. In some instances, the INA expressly authorizes the executive branch to grant certain benefits or relief to aliens. In these instances, aliens are eligible for the benefit or relief not because Congress has given the executive branch discretion to waive restrictions that would otherwise bar the aliens from the benefit or relief, as discussed below (see " Statutory Waivers of Restrictions on Benefits or Relief "), but because Congress has affirmatively provided for certain benefits or relief to be granted. In some cases where Congress has delegated discretionary authority over a particular form of benefit or relief to immigration officials, it has provided clear statutory guidance for when such authority may be exercised. In other cases, there are few, if any, express limits on the authority granted to the executive, although some would argue that prior uses of particular authorities should serve to constrain subsequent uses of this authority. The authority to grant benefits or relief can play a significant role in executive discretion as to immigration, as the examples below illustrate. Temporary protected status (TPS) is a type of relief from removal that Congress has authorized the executive branch to grant to aliens who presently cannot be safely returned to their home countries. Section 244 of the INA imposes a number of conditions upon who may be granted TPS. Specifically, aliens must be from a foreign state that the Department of Homeland Security (DHS) has designated due to an ongoing armed conflict; an earthquake, flood, drought, epidemic, or other environmental disaster; or other "extraordinary and temporary conditions" that prevent aliens' safe return; have been "continuously physically present" in the United States since the effective date of their home country's most recent TPS designation; have "continuously resided" in the United States since whatever date the executive may designate (generally a date that is earlier than the TPS designation date); be generally admissible as an immigrant and not ineligible for TPS (e.g., have not been convicted of specified offenses); register during the period prescribed for registration by the executive branch; and pay any registration fee required by the executive branch. In addition, Congress has provided that TPS is generally to be withdrawn if the alien proves to have been ineligible for such status; has not remained "continuously physically present" since the date he or she was first granted TPS; or fails "without good cause" to register annually. Despite these conditions, a grant of TPS can afford significant relief to individual aliens because aliens with TPS are provided identifying documentation and work authorization by the executive branch, and they cannot be removed while they have TPS. TPS can also be a powerful tool for the executive in crafting immigration policy. For example, TPS could be used to enable aliens who are from countries where large numbers of persons have been displaced, but are unlikely to qualify as refugees, to remain in the United States. Further, while TPS is "temporary," in practice, aliens from designated countries are often able to remain and work in the United States for years, potentially prompting further migration from the country. Another example of discretionary authority to grant benefits or relief conferred by statute involves employment authorization documents (EADs) permitting aliens to work legally in the United States. In general, the INA provides that only specified categories of aliens are eligible to obtain employment in the United States, and Section 274A of the INA bars the hiring or continued employment of "unauthorized aliens." The definition of unauthorized alien found in Section 274A describes an unauthorized alien , in part, as an alien who is not "authorized to be ... employed ... by the Attorney General [currently, the Secretary of Homeland Security]." This language has historically been seen as affording immigration officials at least some discretion to grant EADs to aliens, including those without lawful immigration status. There are no express conditions contained in the INA regarding when the Secretary of Homeland Security may grant work authorization, and the executive branch has promulgated regulations that provide for the issuance of EADs to aliens who have been granted various—and often temporary—forms of relief from removal, including deferred action and deferred enforced departure. Work authorization regulations promulgated by immigration officials have played an important role in the Obama Administration's 2012 Deferred Action for Childhood Arrivals (DACA) initiative. Because DHS regulations had already provided for the issuance of EADs to aliens granted deferred action when such aliens establish "an economic necessity for employment," DACA beneficiaries were effectively made eligible for EADs as a corollary of receiving deferred action. Further, because many states have laws providing for the issuance of driver's licenses to aliens whose presence in the United States is "authorized" under federal law, and accept EADs as proof that an alien's presence is so authorized, DACA beneficiaries generally also became eligible to obtain driver's licenses in the states where they were residing. Subsequently, however, in its 2015 decision in Texas v. United States , a majority of the U.S. Court of Appeals for the Fifth Circuit found that the Obama Administration's proposal to expand the DACA program and create a DACA-like program for aliens who are the parents of U.S. citizens or LPRs is inconsistent with or, alternatively, constitutes an unreasonable interpretation of, the INA's provisions regarding work authorization, among other things. In so finding, the majority specifically noted that the DACA-like program—commonly known as Deferred Action for Parents of Americans (DAPA)—would "dramatically increase the number of aliens eligible for work authorization, thereby undermining Congress's stated goal of closely guarding access to work authorization and preserving jobs for those lawfully in the country." The Supreme Court granted the federal government's petition for review of the Fifth Circuit's decision. However, an evenly divided Supreme Court ultimately issued a decision that, consistent with recent practice, affirmed the Fifth Circuit's decision without any opinion or indication of the Justices' voting alignment. In some cases, the INA provides immigration officers with discretionary authority to waive statutory requirements that would otherwise render a particular alien ineligible to receive an immigration-related benefit or form of relief. Typically, a discretionary waiver permits immigration authorities to exempt application of some, but not all, of the eligibility requirements that an alien must otherwise satisfy. Judicial review of decisions to exercise waiver authority is typically limited and, in some cases, is largely barred by statute. However, federal courts may review questions of law raised by the executive's use of waiver authority (e.g., whether immigration authorities properly found that an alien is statutorily ineligible for a waiver). The parameters of any waiver authority are controlled by the terms of the relevant statute, but where that statute is silent or ambiguous, the executive could be said to have some discretion in determining how the waiver is applied. For example, among the actions that the Obama Administration announced in November 2014 was "clarifying" what is meant by "extreme hardship" for purposes of the provisions in Section 212(a)(9)(B)(v) of the INA, which permit immigration officials to waive the 3- and 10-year bars upon the admission of an alien who has been unlawfully present in the United States for more than 180 days, if denying the alien admission would result in "extreme hardship" to qualifying relatives who are U.S. citizens or LPRs. Arguably some of the most significant examples of discretionary waiver authority involve application of the grounds of inadmissibility listed in Section 212 of the INA. In general, an alien who has not been lawfully admitted into the United States is subject to exclusion or removal from the country if the alien is inadmissible under Section 212. Some grounds of inadmissibility constitute permanent bars to an alien's admission into the United States, such as those applicable to aliens who have committed specified criminal offenses or who have sought to procure an immigration benefit through fraud or misrepresentation. In other cases, a ground of inadmissibility may bar an alien from being admitted into the United States for a certain period of time. For instance, an alien who departs or is removed from the United States after having been unlawfully present in the country for more than 180 days is generally inadmissible for a specified number of years after he or she departs or is removed. The INA provides immigration authorities with the ability to waive application of many of these grounds in certain situations, and thereby enable otherwise-excludable aliens to be lawfully admitted into the United States. Most notably, the immigration authorities have discretion to waive most of the inadmissibility grounds with respect to applicants for nonimmigrant visas , so that such aliens may be permitted to enter the United States on a temporary basis. An alien who obtains such a waiver remains ineligible to receive an immigrant visa allowing him or her to come to the United States on a permanent basis, and would also be unable to adjust to LPR status while present in the United States on a nonimmigrant visa, barring further waivers. Immigration officials may also waive certain grounds of inadmissibility so that aliens may be admitted into the United States on immigrant visas and/or permitted to adjust to LPR status in certain instances. Examples include the following: Section 212(a)(9)(B)(v) permits the waiver of the inadmissibility provision applicable to aliens who have been unlawfully present in the United States for more than 180 days, if immigration authorities determine that refusing to admit the alien would result in "extreme hardship" for a U.S. citizen or LPR who is the spouse or parent of the alien. Section 212(h) generally authorizes immigration officers to waive many of the inadmissibility grounds concerning criminal activity for qualifying aliens, including those (1) whose convictions for the criminal offenses rendering them inadmissible occurred more than 15 years before the date of the alien's application for a visa, admission, or adjustment of status, and who are deemed rehabilitated and not a threat to U.S. welfare, safety, and security; or (2) whose denial of admission would result in "extreme hardship" for a U.S. citizen or LPR who is the spouse, parent, or child of the alien. However, the eligibility for waivers of aliens who had previously been admitted as LPRs and lost such status, and thereafter seek to be readmitted as LPRs or adjust to LPR status, is circumscribed. Section 212( i ) permits the waiver of the ground of inadmissibility applicable to aliens who procured or sought to procure an immigration benefit through fraud or misrepresentation, when it is determined that the denial of the alien's lawful admission would result in "extreme hardship" to a U.S. citizen or LPR who is the spouse or parent of the alien. Former Section 212(c) gave immigration officials discretion to waive most grounds of inadmissibility with respect to LPRs who had temporarily proceeded abroad and sought reentry into the United States, provided that the LPR had been domiciled in the United States at least seven years and met certain other conditions (i.e., had not served at least five years' imprisonment for an aggravated felony conviction, and was not inadmissible on grounds relating to national security or international child abduction). This waiver authority had also been construed by immigration officials and reviewing courts to apply to LPRs who were present in the United States and undergoing deportation hearings. Although this waiver provision was deleted from the INA in 1996, courts have construed such authority as remaining available to immigration officials with respect to resident aliens who are removable on account of guilty pleas arising prior to the repeal of Section 212(c). While not typically characterized as a waiver, Section 212(d)(5) of the INA gives immigration officials broad discretion to permit aliens to enter or remain in the United States, at least temporarily, notwithstanding the fact that the alien may be otherwise inadmissible. As previously discussed, the INA authorizes immigration officials to waive certain grounds of inadmissibility, and thereby permit excludable aliens to be admitted into the United States as immigrants or nonimmigrants. In contrast, the parole of an alien into the United States does not constitute "admission" for immigration purposes. Despite the paroled alien's physical presence in the country, the alien is "still in theory of law at the boundary line" of the United States, and does not have a legal immigration status. Nonetheless, some aliens who obtain parole may be able to adjust to lawful permanent resident (LPR) status while present in the United States (provided they are not covered by a ground of inadmissibility, or any applicable ground of inadmissibility is waived). Aliens granted parole may also, under current regulations, be granted work authorization. The use of parole authority has been authorized by statute since the INA was originally enacted in 1952. Over the years, the statutory language concerning parole authority has been amended somewhat, but the focus has remained upon those persons whose entry into the country is deemed warranted due to pressing "humanitarian" concerns, or because the alien's entry is in the "public interest." The INA currently permits the Secretary of Homeland Security to parole aliens into the United States "only on a case-by-case basis for urgent humanitarian reasons or significant public benefit," and further restricts the usage of parole with respect to alien crewmembers or refugees. As noted in the text box below, parole authority has been exercised by the executive branch to permit the entry of various groups of aliens into the United States. In addition, "advance parole" has been used to permit certain non-LPR aliens who are physically present within the United States to reenter the United States after a brief departure (e.g., nonimmigrants whose visa does not permit readmission; aliens who lack lawful immigration status but have been permitted to remain in the country). "Parole-in-place" has also been granted to some aliens who are physically present within the United States, but lack a legal immigration status, most notably, the spouses, children, or parents of those serving, or who previously served, on active duty in the U.S. Armed Forces or the Selected Reserve of the Ready Reserve. Once granted parole-in-place, such aliens are no longer seen as unlawfully present and may be eligible to adjust status pursuant to Section 245 of the INA, as discussed below (see " Adjustment of Status by Aliens Granted Advance Parole "). Among the actions announced by the Obama Administration in November 2014 is the paroling of certain inventors, researchers, and entrepreneurs into the United States on the grounds that their entry will provide "significant public benefit." Other actions involve greater consistency in determinations as to whether to grant advance parole, and the parole of certain unlawfully present spouses, children, and parents of U.S. citizens and LPRs seeking to enlist in the armed forces. As these examples suggest, exercises of affirmative authority to grant benefits or relief, or to waive restrictions on benefits or relief, must be consistent with any statutory limitations. For example, the executive is arguably barred from considering "hardship" to the alien, or to the alien's children, in determining whether to waive the 3- and 10-year bars upon the admissibility of aliens who have accrued at least 180 days of unlawful presence in the United States because Section 212(a)(9)(B)(v) of the INA expressly refers to waivers: in the case of an immigrant who is the spouse or son or daughter of a United States citizen or of an alien lawfully admitted for permanent residence, if it is established ... that the refusal of admission to such [an] alien would result in extreme hardship to the citizen or lawfully resident spouse or parent of such alien. However, in cases where the INA is silent or ambiguous, the executive could potentially have more discretion as to how affirmative authority to grant benefits or relief, or waive restrictions on benefits or relief, is exercised. (See "Discretion in Interpreting and Applying Statutes.") In addition, even where there are few, if any, statutory restrictions upon the executive's ability to grant immigration-related benefits or relief, questions might be raised about whether particular exercises of authority are consistent with historical practice, other provisions of the INA, or Congress's intent in granting the executive branch specific authority. For example, while nothing in the INA expressly prohibits the executive branch from doing so, granting EADs to every alien who comes to the United States, regardless of such alien's legal status, would be unprecedented. Similarly, if the executive hypothetically were to propose granting work authorization to all aliens coming to the United States, an argument could be made that doing so would be inconsistent with the provisions that Congress made in the INA for the protection of domestic labor in the granting of employment-based immigrant and nonimmigrant visas. An argument could also be made that Congress is unlikely to have defined unauthorized alien and prohibited the knowing hiring or employment of such aliens if it contemplated the executive branch granting work authorization to all aliens. The executive is generally recognized as possessing some degree of independent authority in assessing when, against whom, how, and even whether to prosecute apparent violations of federal law; an authority generally referred to as "prosecutorial discretion" or "enforcement discretion." Such authority has been seen to exist in the field of immigration, and to grant the executive some discretion in determining, among other things, whether to commence removal proceedings and the nature of the particular charges to lodge against an alien; whether to cancel a Notice to Appear (NTA) or other charging document before jurisdiction vests with an immigration judge; and whether to appeal an immigration judge's decision or order. The granting of immigration benefits, in contrast, has historically been seen not as an exercise of prosecutorial or enforcement discretion inherent to the executive branch, but as an exercise of authority expressly delegated by Congress. The exercise of prosecutorial or enforcement discretion in specific cases has historically been based on humanitarian factors, or resources constraints. A "favorable" exercise of discretion (e.g., one permitting a potentially removable alien to remain in the United States) generally does not grant the alien a legal immigration status, despite the alien having official permission to remain in the country. However, by enabling the alien to remain in the United States, a favorable exercise of discretion could permit the alien to acquire a basis for legalization in the future (e.g., the establishment of ties that would provide a basis for adjustment of status under current law, or following the enactment of a legalization measure like the Immigration Reform and Control Act of 1986). One example of the executive's prosecutorial or enforcement discretion as to immigration involves determinations as to whether to issue Notices to Appear (NTAs) or other charging documents initiating proceedings against individual aliens who are believed to be removable. Such discretion has likely been used as long as there have been grounds for deporting or removing aliens, with individual immigration officers determining that humanitarian factors or resource constraints were such that action against specific individuals was not warranted. A few "large scale" examples have also been noted, such as the then-INS's determination in 1962 to permit "56,800 refugee overstay visitors [from Cuba] ... to remain in the United States for an indefinite period," rather than seeking their removal. (These persons were apparently separate and apart from the 62,500 Cuban parolees, and the 6,500 Cubans in visitor status, also reported that year as having been permitted to remain in the United States indefinitely). However, there is only sporadic evidence regarding such uses of discretion until the mid-1970s, when the executive branch began issuing memoranda that elaborated on specific aspects of immigration enforcement and, particularly, its practices and priorities as to immigration enforcement. Currently, for example, these memoranda establish a general policy of not engaging in arrests, interviews, searches, or surveillance for purely immigration enforcement purposes near schools or churches. Conversely, the "highest priority" is given to the removal of (a) aliens engaged in or suspected of terrorism or espionage, or who otherwise pose a danger to national security; (b) aliens apprehended at the border or ports of entry while attempting to unlawfully enter the United States; (c) aliens convicted of an offense for which an element was active participation in a criminal street gang, as defined in 18 U.S.C. §521(a), or aliens not younger than 16 years of age who intentionally participated in an organized criminal gang to further the illegal activity of the gang; (d) aliens convicted of an offense classified as a felony in the convicting jurisdiction, other than a state or local offense for which an essential element was the alien's immigration status; and (e) aliens convicted of an "aggravated felony," as that term is defined in section 101(a)(43) of the INA at the time of the conviction. Amending DHS's enforcement priorities—to establish the listing given above—was one of the actions taken by the Obama Administration in 2014. It is important to note that this action has not been affected by the injunction barring implementation of the DAPA program and DACA expansion. To the contrary, both the Fifth Circuit and the district court in Texas v. United States expressly noted that the executive's enforcement priorities are not at issue in that case and are within DHS's discretion. The Administration also took action in November 2014 to discontinue its former Secure Communities program and replace it with the Priority Enforcement Program (PEP). Like Secure Communities, PEP will rely upon information sharing between various levels and agencies of government to identify potentially removable aliens. However, unlike Secure Communities, PEP will focus primarily on aliens who have been convicted of felonies or "significant" misdemeanors, and generally will not entail states and localities holding aliens after they would have otherwise been released for the state or local offense that prompted their initial arrest so that DHS can take custody of them. These changes can also be seen as changes in enforcement priorities. Another example of discretion in enforcing immigration law involves the granting of deferred action to removable aliens. Grants of deferred action date back to at least the 1970s, and are distinct from determinations not to issue NTAs or take other enforcement action. Historically there has been no record of an immigration officer's determination not to issue an NTA, and one immigration officer's determination not to issue an NTA to an individual alien has generally not been seen as "binding" on other officers encountering the same alien. The situation is different as to grants of deferred action, which are documented in the alien's immigration file (commonly known as the "A file"), and have historically been seen to govern unless and until there are changes in the alien's circumstances. Immigration officials may grant deferred action on their own initiative, or aliens can request deferred action if they know it is an option. Perhaps the best known examples of deferred action involve the Obama Administration's 2012 DACA initiative, along with the Administration's 2014 announcement of a planned expansion of DACA and the creation of a DACA-like program for unlawfully present aliens who are the parents of U.S. citizens or LPRs, known as "DAPA." However, these deferred action programs arguably differ from prior grants of deferred action in that the availability of deferred action is widely known, and the factors considered in determining whether to grant it are explicit. Additionally, grants of deferred action through DACA and DAPA (if implemented) last for a specified period of time (two years under the 2012 DACA initiative, three years under the proposed DAPA program and DACA expansion), with the possibility of renewal, as opposed to being open-ended like grants of deferred action outside DACA and DAPA (if implemented) potentially are. Some have also said that grants of deferred action through DACA and DAPA are to be seen as different in that these initiatives involve "categories" of aliens. However, the Obama Administration has emphasized that determinations as to whether to grant deferred action through DACA and DAPA are to be made on an individual basis, and that no one is "entitled" to deferred action through these initiatives, even if all "the guidelines [suggesting the alien warrants a favorable exercise of discretion] are met." The Administration has also continued to grant deferred action to aliens outside the DACA initiative and the proposed DACA expansion and DAPA initiatives, although on a smaller scale. The Obama Administration has been enjoined from implementing DAPA and the DACA expansion, as discussed below. However, this order did not enjoin the 2012 DACA initiative or the granting of deferred action in individual cases outside of DACA and DAPA. The executive branch's enforcement discretion is subject to two notable limits, neither of which is necessarily judicially enforceable in particular cases. The first is that the express adoption of a policy that constitutes an abdication of a statutory duty could be found to be impermissible under the rationale articulated by the Supreme Court in its 1985 decision in Heckler v. Cheney . The Heckler Court expressly recognized the possibility of an executive agency "consciously and expressly adopt[ing] a general policy [of not enforcing the law] that is so extreme as to amount to an abdication of its statutory responsibilities." However, the Heckler Court did not elaborate upon what might constitute such an abdication, and at least one federal court of appeals later took the view that "[r]eal or perceived inadequate enforcement ... does not constitute a reviewable abdication of duty." Instead, the appellate court opined that the plaintiffs must show that the executive either is "doing nothing to enforce the ... laws," or has "consciously decided to abdicate" its enforcement responsibilities. More recently, however, the federal district court hearing a challenge to the 2014 DAPA initiative and the expansion of DACA brought by 26 states or their representatives distinguished this case from prior cases involving the federal government's alleged failure to enforce the immigration laws on the grounds that the 2014 actions involve "abdication by any meaningful measure," not "mere ineffective enforcement." In so doing, the court seems to have been influenced by the government's explicit announcement that it would not be seeking the removal of certain aliens, as well as the sheer number of aliens eligible for the 2014 deferred action initiatives. The court did not, however, find that the plaintiffs could maintain their challenge based solely on "the concept of abdication standing." Further, its decision to enjoin the Administration from implementing the 2014 deferred action initiatives was based on its finding that the initiatives constituted a "substantive rule," but had been promulgated without compliance with the notice-and-comment requirements of the Administrative Procedure Act (APA); not because they constituted an "abdication" of the executive's statutory duties. A majority of the Fifth Circuit subsequently affirmed the district court's decision, but without directly addressing the question of whether DAPA and the DACA expansion represent an "abdication" of the executive's statutory duties. Instead, the Fifth Circuit majority found that these programs violate the APA substantively, as well as procedurally. The district court had found a procedural violation of the APA, as previously noted. However, the Fifth Circuit majority went beyond the district court to find a substantive violation of the APA, on the grounds that Congress had spoken to the precise questions at issue here—namely, the granting of relief from removal and work authorization to aliens who had entered or remained in the United States in violation of federal immigration laws—in such a way as to preclude DAPA and the DACA expansion. Alternatively, the majority found that even if Congress is not seen to have spoken on the precise questions at issue, the executive's interpretation is "unreasonable" because it is "manifestly contrary" to the INA provisions regarding (1) which aliens may lawfully enter and remain in the United States; (2) discretionary relief from removal; and (3) work authorization. It also rejected the view that DAPA and the DACA expansion are grounded in historical practices to which Congress can be seen to have acquiesced by not taking action to bar the practices. The Fifth Circuit's decision here was affirmed by an evenly divided Supreme Court, as previously noted. The second limitation involves specific statutory mandates that particular exercises of prosecutorial or enforcement discretion could be seen to violate. For example, in 2012, a federal district court found that DACA runs afoul of three purportedly "interlocking provisions" in Section 235 of the INA which the court construed as requiring that all aliens who have not been "admitted" into the United States be placed in removal proceedings. These provisions state that 1. any alien present in the United States who has not been admitted shall be deemed an applicant for admission; 2. applicants for admission shall be inspected by immigration officers; and 3. in the case of an alien who is an applicant for admission, if the examining immigration officer determines that an alien seeking admission is not clearly and beyond a doubt entitled to be admitted, the alien shall be detained for removal proceedings. Each provision uses "shall," which the court viewed as indicating "mandatory" agency action. This court later dismissed the case on jurisdictional grounds, a decision which was upheld on other grounds by the Fifth Circuit. The Fifth Circuit did not directly address the interpretation of Section 235 of the INA in its decision in Crane . However, in its "background" discussion of the immigration laws, the Fifth Circuit opined that Section 235 at most, "directs" immigration agents to "detain" aliens for the purpose of placing them in removal proceedings. "It does not limit the authority of [the Department of Homeland Security] to determine whether to pursue the removal" of the alien once they have been so detained, in the Fifth Circuit's view. It is important to note, however, that not all statutes using "shall" have been construed to eliminate executive discretion, particularly in cases where the statute prescribes that persons be sanctioned for particular violations. For example, in a 2011 decision, the Board of Immigration Appeals (BIA), the highest administrative body for construing and applying immigration law, found that immigration officers have discretion as to whether to pursue expedited removal proceedings under Section 235 or formal removal proceedings under Section 240 of the INA, notwithstanding the fact that the INA uses "shall" in describing who is subject to expedited removal. In so doing, the BIA specifically noted that, in the Federal criminal code, Congress has defined most crimes by providing that whoever engages in certain conduct "shall" be imprisoned or otherwise punished. But this has never been construed to require a Federal prosecutor to bring charges against every person believed to have violated the statute. Another type of discretion that the executive branch may exercise as to immigration law involves the interpretation and application of statutes. As the Supreme Court explained in its 1984 decision in Chevron U.S.A. v. Natural Resources Defense Council , when "Congress has directly spoken to the issue, ... that is the end of the matter; for the court, as well as the agency, must give effect to the unambiguously expressed intent of Congress." However, where a statute is "silent or ambiguous with respect to a specific issue," courts will generally defer to an agency interpretation that is based on a "permissible construction of the statute," on the grounds that the executive branch must fill any "gaps" implicitly or explicitly left by Congress in the course of administering congressional programs. The degree of deference afforded to particular executive branch interpretations can vary depending upon the facts and circumstances of the case, including whether the interpretation is a "formal" one adopted through notice-and-comment rulemaking or case-by-case adjudication. There are a number of places where the INA or other immigration-related statutes are silent or ambiguous on particular issues, and the executive branch has—expressly or practically—adopted an interpretation that significantly affects the implementation of immigration law. As some commentators have suggested, these executive branch interpretations can be changed to expand (or restrict) aliens' ability to enter or remain in the United States, or the conditions of their continued presence here, without the enactment of additional legislation. One example of the executive's discretion in interpreting and applying the law involves the provisions in the Personal Responsibility and Work Opportunity Reconciliation Act (PRWORA) which restrict noncitizens' eligibility for "federal means-tested public benefits" and other public benefits. PRWORA itself does not affirmatively define what constitutes a "federal means-tested public benefit." Rather, it excludes certain benefits (e.g., some emergency disaster relief) from the application of the general bar upon the receipt of such benefits by LPRs and other "qualified aliens" during their first five years after entering the United States in a qualified status. Instead, the executive branch, through the promulgation of regulations, has determined that "federal means-tested public benefits" encompasses only Supplemental Security Income (SSI), Temporary Assistance for Needy Families (TANF), Medicaid, food stamps, and the state Child Health Insurance Program (SCHIP), not other benefits. Some have questioned the executive's determination to include only these mandatory spending programs, and not any discretionary ones, in defining "federal means-tested public benefits" for purposes of PRWORA. However, the Office of Legal Counsel (OLC) at the Department of Justice has opined that the executive's regulations here would likely be viewed as entitled to deference by a court, since the statutory text is ambiguous, and the agency's construction is a reasonable one. In so doing, OLC acknowledged that "[s]everal aspects of the text and legislative history of [PRWORA], when viewed in isolation," could potentially be said to "support a broad[er] interpretation of 'federal means-tested public benefit' that would include discretionary programs." However, OLC viewed these factors as carrying less weight than Congress's ultimate decision not to incorporate a definition of "federal means-tested public benefits" that encompassed discretionary spending programs in the text of PRWORA, as enacted. OLC cited, in support of this conclusion, the "well-settled canon of interpretation that 'where the final version of a statute deletes language contained in an earlier draft, [it may be presumed] that the earlier draft is inconsistent with ultimate congressional intentions." It also pointed to several provisions that had been struck from the Senate-passed version of PRWORA on the grounds that they were extraneous, and subsequently been reintroduced by the conference committee. The definition of "federal means-tested public benefits" was not one of these. OLC further suggested that PRWORA ought to be construed in light of the rules governing reconciliation that shaped its enactment, which foreclosed consideration, in that context, of provisions affecting discretionary spending. No court to date appears to have taken a different view than OLC on this question. Another example of discretion in interpreting and applying statutes concerns the question of whether aliens who have accrued more than 180 days of unlawful presence in the United States may adjust to LPR status if granted advance parole. Section 245 of the INA permits immigration officials to adjust the status of status of aliens who were "inspected and admitted or paroled" and are "admissible for permanent residence," among other things. A grant of advance parole would appear to constitute being "paroled" for purposes of Section 245. However, Section 212(a)(9)(B)(i) of the INA provides that aliens who "depart" the United States after accruing more than 180 days of unlawful presence are inadmissible for three to ten years after departing and was, until recently, seen to render aliens who left the United States pursuant to a grant of advance parole inadmissible and, thus, ineligible for adjustment of status. This view resulted, in part, because the BIA had construed "departure" broadly in its 2007 decision in Matter of Lemus : to encompass any 'departure' from the United States, regardless of whether it is a voluntary departure in lieu of removal or under threat of removal, or it is a departure that is made wholly outside the context of a removal proceeding. Five years later, though, the BIA revisited the meaning of "departure" for purposes of Section 212(a)(9)(B)(i) in its 2012 decision in the consolidated cases of Matter of Arrabally and Matter of Yerrabelly . There, the BIA adopted a narrower construction that opens the door for at least some aliens granted advance parole to adjust their status pursuant to Section 245 of the INA. The BIA did so by first noting that its earlier decision in Matter of Lemus involved an alien who had accrued more than one year of unlawful presence in the United States and then departed the country without obtaining advance permission to return. Thus, in the BIA's view, his situation was distinguishable from that of aliens in Matter of Arrabally and Matter of Yerrabelly , who had left the United States pursuant to a grant of advance parole. This difference prompted the BIA to conclude that its "unqualified declaration in Lemus ... that inadmissibility under Section 212(a)(9)(B)(i)(II) could be triggered by literally 'any departure' from the United States has had implications that bear additional consideration." Upon further consideration of these implications, the BIA found that Congress had not intended Section 212(a)(9)(B)(i) to apply to aliens who left and returned to the United States pursuant to a grant of advance parole. Thus, it held that aliens who leave the United States pursuant to a grant of advance parole do not make a "departure" from the United States for purposes of Section 212(a)(9)(B)(i). Interpretations set forth in BIA decisions, like those discussed here, are afforded the same deference under Chevron as agency regulations. Although these examples illustrate that the executive branch may have some discretion in interpreting and applying immigration law when the INA is silent or ambiguous on particular issues, this discretion is not unlimited. As previously noted, the executive branch's interpretation may be constrained if Congress has directly spoken to the precise question at issue. Moreover, even if Congress has not spoken on the question, the executive branch's interpretation must still be seen as constituting a "permissible" and "reasonable" interpretation of the underlying statute in order to be afforded deference by the courts. Concerns could also be raised about the deference to be accorded to new agency interpretations that are inconsistent with a long-standing interpretation of the agency, particularly an interpretation that third-parties have relied upon. The Supreme Court rejected the view that "inconsistency" in agency regulations is a "basis for declining to analyze the agency's interpretation under the Chevron framework" in its 2005 decision in National Cable & Telecommunications Association v. Brand X Internet Services . However, in so doing, it noted that any "[u]nexplained inconsistency" could be a "reason for holding a regulatory interpretation to be an arbitrary and capricious change from agency practice under the Administrative Procedure Act." Subsequently, questions were raised about the permissibility of changes in certain informal interpretations of agency regulations. However, in its 2015 decision in Perez v. Mortgage Bankers Association , the Supreme Court unanimously found that an agency need not undergo notice-and-comment rulemaking procedures when modifying an interpretive rule. Some may also argue that certain executive actions as to immigration implicate the "major policy" exception to the general principle of Chevron deference in cases where the executive's interpretation could be said to mark a significant change in policy that Congress arguably did not directly contemplate. Such an exception is generally grounded in the Supreme Court's statement, in its 2000 decision in FDA v. Brown & Williamson that "Congress could not have intended to delegate a decision of such economic and political significance [as whether to regulate tobacco pursuant to delegated authority to regulate 'drugs'] to an agency." The Brown & Williamson Court also suggested there may be reason to deny deference in all "extraordinary cases" that involve "major questions." Subsequently, the Supreme Court's 2007 decision in Massachusetts v. EPA was widely seen to have limited, if not vitiated, the "major policy" exception by requiring the executive to implement an arguably major policy adopted by the Environmental Protection Agency through regulations rather than by statute. However, the "major policy" exception factored prominently in the Supreme Court's 2015 decision in King v. Burwell construing the Affordable Care Act (ACA). The Fifth Circuit relied upon this exception in concluding that the executive's interpretation of the INA as permitting DAPA and the DACA expansion is unreasonable, and that the programs exceed the executive's authority. Whether particular actions within the field of immigration are within the executive's authority has long been of interest to Congress. Certain actions announced by the Obama Administration in November 2014 have prompted particular questions about this topic. However, similar questions arose in the past as to specific executive actions, and seem likely to recur in the future. Whether particular actions are within the executive's existing authority depends upon whether these actions can be seen to fall within one (or more) of the three broad types of discretion that the executive is generally seen to have as to immigration. Namely, (1) express delegations of discretionary authority; (2) discretion in enforcement (commonly known as prosecutorial or enforcement discretion); and (3) discretion in interpreting and applying statutes. Each of these three types of authority is subject to certain constraints. For example, exercises of statutory authority must be consistent with the terms of the delegation (although the executive branch could have some discretion in interpreting the statute). Similarly, the executive's exercise of prosecutorial or enforcement discretion could be limited by specific statutory mandates that the executive take particular actions (e.g., detaining certain aliens pending removal proceedings). The express adoption of a policy that constitutes an abdication of a statutory duty could also be found to be impermissible, although it might be difficult for a court to assess whether an alleged failure to enforce the law constitutes an "abdication." Likewise, agencies' interpretations and applications of statutes must conform to the "unambiguously expressed intent of Congress."

Summary: The scope of the executive's discretion in implementing federal immigration law is a topic of perennial interest to Members and committees of Congress. Most recently, questions have been raised as to whether particular actions announced by the Obama Administration in November 2014 are within the executive's authority. See generally CRS Legal Sidebar WSLG1442, The Obama Administration's November 20, 2014, Actions as to Immigration: Pending Legal Challenges One Year Later, by [author name scrubbed]. However, similar questions were raised in the past about other executive actions including, but not limited to (1) suspending enforcement of certain provisions of the Immigration and Nationality Act (INA) in areas affected by natural disasters; (2) granting deferred enforced departure, extended voluntary departure, or other relief from removal to certain aliens who entered or remained in the United States in violation of the INA; and (3) "paroling," or permitting the entry of, certain aliens into the United States who were not admissible under current law. Whether particular executive actions are permissible generally depends upon whether they can be seen as falling within one (or more) of the three broad types of authority that the executive can be seen to have as to immigration. These include the following: Express delegations of discretionary authority by statute. In some cases, the INA explicitly authorizes the executive to provide certain relief or benefits to foreign nationals (e.g., temporary protected status or work authorization). In other cases, the INA expressly permits immigration authorities to waive the application of requirements which would render an alien ineligible for particular immigration benefits. The INA also grants the executive broad authority to "parole" aliens into the United States. Discretion deriving from the executive's independent constitutional authority. The executive is generally recognized as possessing some degree of independent authority in assessing whether to prosecute apparent violations of federal law. Courts have recognized certain actions as within the prosecutorial or enforcement discretion of immigration authorities. These include deciding whether to issue a Notice to Appear beginning removal proceedings; deciding whether to detain aliens who are not subject to "mandatory detention" pending removal; and granting deferred action (at least in individual cases). Discretion in interpreting and applying immigration law. The Supreme Court has found that some deference may be owed to agency regulations (or adjudications) which implement or apply statutes that are "silent or ambiguous" as to specific issues. The executive branch may also be afforded deference in less formal interpretations of statutes and in interpreting its own regulations. All of these forms of discretion are subject to certain constraints. For example, exercises of statutory authority must be consistent with the terms of the delegation (although the executive branch could have some discretion in interpreting the statute). Similarly, the executive's exercise of prosecutorial or enforcement discretion could be limited by specific statutory mandates that the executive take particular actions (e.g., detaining certain aliens pending removal proceedings). The express adoption of a policy that constitutes an "abdication" of a statutory duty could also be found to be impermissible, although it might be difficult for a court to assess whether an alleged failure to enforce the law represents an abdication. Likewise, agencies' interpretations and applications of statutes must conform to the "unambiguously expressed intent of Congress."