How much discretion does the executive branch have over immigration policy?

The president's decision to defer the risk of deportation for several million unauthorized immigrants has prompted substantial debate about the scope of the president's authority. The president unquestionably has broad authority over immigration policy under current law. As The New York Times reported, the administration sought to use this authority quite aggressively.

Following the announcement, the folks at Balkinization hosted a symposium on the scope of the president's administrative discretion over immigration policy. Links to the collected posts, from a range of scholars - including Bruce Ackerman, Marty Lederman, Gillian Metzger, and Zach Price, among others - can be found here. For decidedly less sympathetic takes, see this Wall Street Journal op-ed critiquing the OLC memo on which the administration relied by David Rivkin and Elizabeth Price Foley and this NRO article by former George W. Bush administration attorneys Shannen Coffin and Michael Edney.

In the New Republic, Eric Posner argues that the administration has set a precedent for deregulatory action that Republicans should like (assuming there is a Republican president at some point in the near future). He elaborates on the point and responds to critics here. As a matter of political norms, he is probably correct. As a matter of law, I am not so sure. Immigration law, as it has been understood and implemented for the past several decades, affords the executive branch more discretion than it enjoys in many other areas. Further, Congress retains the ability to curtail this discretion through statutory reform or limitations on appropriations (not that Congress is likely to do either).

As I noted here, it's not enough to look at the scope or scale of an exercise of executive authority to evaluate its legality. The details matter. Specifically, one must consider the nature and character of the executive action, the relevant statutory provisions, and the way these provisions have been construed and implemented over time. The result is that some broad and aggressive actions, such as the president's immigration initiatives (both DACA and the more recently announced policy) may have sounder legal footing than deceptively narrow and discrete actions, such as delaying the employer mandate.

Law matters here, but so do political norms. Much of the debate over the president's immigration action is really about the appropriate use of executive authority, and not about the law. This action is unlikely to be challenged in court successfully. Not only are the merits tough, but it's unlikely anyone has standing. This means the debate will be resolved politically, as it should be.