At Volokh Conspiracy, Ilya Somin: Why the Migration or Importation Clause of the Constitution does not imply any general federal power to restrict immigration. From the introduction:
Some readers of my recent Reason op ed arguing that, under the original meaning of the Constitution, Congress had no general power over immigration, have written to me, pointing to the Migration or Importation Clause, as evidence to the contrary. Some modern advocates of broad congressional power over immigration also cite it to support their position. But, at least under the original meaning of the Constitution, it does not.
I generally agree with the ensuing (extended) argument, though I think it might be stated more simply. Saying that Congress cannot regulate migration prior to 1808 doesn't imply that Congress has full power to regulate migration; it only implies that Congress has some power to regulate migration (which can be exercised after 1808). Congress appears to have some power to regulate migration through its foreign commerce power, because (I would say) it can prohibit or limit the ability of ships operating in foreign commerce to sell passages to migrants. Thus it might be the case that Congress does not have power to regulate some migrants (e.g., those crossing by foot without assistance). Or at least, no having this power is still consistent with the migration clause. (I think it might be located elsewhere, however).
Posted at 8:45 AM