Critics of the plan the president is reported to be considering argue that the Constitution obliges him to “take care that the laws be faithfully executed,” an obligation that seems to give the lawmaker, Congress, the primary authority to set policy. They say that refusing to enforce immigration law against millions of illegal immigrants violates that constitutional duty.

Yet the Constitution also gives the president “executive power,” which has always been understood to include the discretionary power to allocate resources among enforcement efforts. The significance of this power has grown over the last century, as Congress has created vast regulatory agencies and given the president control over them.

Congress typically appropriates money for regulators, gives the president some vague guidelines and enacts far more laws than he could possibly enforce, and then allows him to set enforcement priorities as he sees fit. That’s why different administrations can pursue such different policies from each other without getting Congress’s permission first. The Reagan administration came to power promising to deregulate the economy, which often meant not enforcing the law, whether it was antitrust, environmental or financial.

If, under the Constitution, the president must enforce much of the law but need not enforce all of it, where should the line be drawn?

Read more at The New York Times