I recently participated in a symposium at Michigan State on Immigration Policy in the 21st Century. I spoke on a panel with Ilya Somin, John Eastman, and Mike Ramsey. Our topic: does the federal government have a power over immigration. Ilya has explained the answer is no. My take is different. Congress has the power to exclude, but the answer is not as straightforward as I (and most people) have assumed. I’ve posted my draft paper to SSRN. Here is the abstract:

Under modern doctrine, the federal government has an inherent authority to exclude aliens from entering the United States. In contrast, states lack any power to exclude aliens from entering their own borders. Though well settled, this dichotomy stands in tension with our Constitution’s structural design. It is a bedrock principle that the federal government only has those powers that are enumerated in the Constitution. In many respects, modern doctrine inverts our constitutional order. The states, which have the strongest claim to a general power to exclude cannot exercise that power. Congress, which has the weakest claim to an inherent power to exclude, can exercise that power with few discernible limits.

Does the federal government have the power to exclude aliens? Yes, though the answer is not as straightforward as many of us have assumed. There are four plausible candidates in Article I to support an exclusionary power: the Naturalization, Commerce, Law of Nations, and Migration of Importation Clauses. However, none of these clauses, standing by itself, supports an enumerated power to prevent foreign aliens from entering the United States. Rather, the strongest argument in support of an exclusionary power is an implied authority. It is both “necessary” and “proper” for Congress to restrict entry to aliens in order to more effectively naturalize citizens and, perhaps, regulate commerce. This authority is incidental, and does not “flatten[] the principle of state sovereignty.” Therefore, the exclusionary power does not amount to a “great substantive and independent power” that improperly aggrandizes Congress’s reach over states, their officials, and individual Americans. This authority belongs solely to Congress, and is not an inherent executive power.