Supporters respond that each DACA application is individually adjudicated, in comport with long-standing determinations of deferred action. Moreover, because the president has limited resources appropriated by Congress to execute the immigration laws, an area that clearly touches upon foreign relations and national security, he may use large-scale prosecutorial discretion to manage those limited resources, while simultaneously protecting individuals with no lawful status who are residing in and seemingly contributing to the United States in meaningful ways.
In a 1952 Supreme Court decision, Youngstown Sheet & Tube Co., Justice Robert Jackson, in a concurring opinion, proposed a framework to evaluate the exercise of presidential powers. First, when the president acts pursuant to congressional authorization and his own constitutional authority, the president's authority is at its highest. Second, when the president acts in absence of congressional action, he can rely only upon his own powers, but there is an unknown zone of twilight where he and Congress may have concurrent authority, or where the president's authority is simply unclear. Third, when the president's actions are incompatible with the will of Congress, his power is at its lowest ebb; in this situation, the president can rely only upon his own constitutional authority minus any congressional authority.
In granting large-scale reprieves to people without lawful status in the U.S., is the president acting pursuant to congressional authority, where his power is at its peak, or is the president acting contrary to congressional authority, where his power is at its lowest? Or is the president acting in the absence of any congressional action?
With clear congressional authorization for the executive branch to grant aliens admission into the U.S., and also to remove them, it would be difficult to argue that there is an absence of congressional action here. It is less difficult, but difficult nonetheless, to argue that the president is acting pursuant to congressional authorization when he acts on a broad scale to grant deferred action to a group of people. For example, Congress may appropriate more money for immigration enforcement next year, but the DACA program would still prohibit government officials from removing its beneficiaries. Moreover, implementing the DACA program itself requires refocusing, if not subverting, resources that would otherwise go elsewhere in the immigration scheme.
Nevertheless, the courts have generally recognized that the president has discretion in executing the law. The question is: How far does that discretion extend? If the express will of Congress is for immigration authorities to remove people unlawfully present from the U.S., with some noted exceptions, it is not necessarily true that because Congress has not allocated enough money to remove every unlawfully-present individual this very year that we may assume that Congress has authorized the president to exercise large-scale reprieves on a rolling basis. To the contrary, critics might argue that it is probably safer to assume that Congress expects ICE to do what it can this year and then to do what it can next year and so on.