Immigration and the Constitution

The Open Borders blog – one of the best websites covering immigration issues – asked me to do a guest post on the implications of the Constitution to debates over immigration. The post is available here. Here is the intro:

The US Constitution does not in itself tell us what kind of immigration policy is right and just. But it is relevant to debates over immigration in at least three important ways. First, some opponents of increased immigration mistakenly argue that the Preamble and other parts of the Constitution commit the US government to ignoring the potential benefits of immigration to would-be migrants themselves. Second, there is a strong case that the original meaning of the Constitution restricts Congress’ power to limit migration, though it does give Congress broad power to deny citizenship to migrants. Finally, some structural aspects of the Constitution help limit the potential “political externalities” of open immigration, thereby weakening claims that the only way to prevent immigrants from having negative effects on public policy is to keep them out of the country entirely.