This slim volume (fewer than 20,000 words; it can be read in under an hour) is a shortened version of a forum published in 2009 in the Boston Review, a bimonthly magazine (also available online), on the question whether undocumented immigrants can acquire “the right to stay.” A lead article by Joseph H. Carens makes the case that liberal democracies are morally obligated to offer a form of amnesty for undocumented migrants who have lived in the country for a certain period of time, and is followed by six short responses (by Mae M. Ngai, Carol M. Swain, Douglas S. Massey, Linda Bosniak, Jean Bethke Elshtain, and T. Alexander Aleinikoff), most of which are sympathetic to Carens's position. The original forum contained responses by nine other people, plus a separate rejoinder by Carens which seems to have been partially integrated here into the text of the lead article.

The key idea behind Carens's arguments is that even if we grant that sovereign states retain the “right to determine whom it will admit and the right to apprehend and deport migrants who settle without official authorization,” states may nevertheless be “morally obligated” to allow long-settled irregular migrants (people who entered the country without official authorization) to remain in the country. In Carens's view, irregular migrants can thus acquire membership rights merely by “making a life” in the country, a proposition he illustrates with a number of affecting stories of long-settled but irregular migrants in the United Kingdom and the United States. These people are, for all intents and purposes, Britons or Americans; they did not belong elsewhere, and it would not have been just to expel them to a different country in which they could have had no real social place.

Carens considers in detail some of the potential problems with his proposal, and outlines some of the ways in which he thinks it should be implemented. For example, though Carens grants that the violation of immigration laws is a violation that states have a right to punish (a view that he thinks is widely held, even though he himself does not hold it), he notes that, like many minor legal violations, there should be a statute of limitations on it. And he argues that though the passage of time per se does not establish claims to membership (it is the social ties that a person forms during that time that matter), it would be a mistake to grant too much discretion to the officials charged with enforcing a policy of amnesty to look into an immigrant's life: too much government discretion in applying the policy would violate the commitment of liberal states to treat each person equally.

Other writers have argued that liberal democratic states are in part complicit in encouraging irregular migration and have used this fact to justify a policy of amnesty. Carens agrees that to the extent that states are complicit in encouraging irregular migration, the argument for amnesty is thereby strengthened, but he thinks that the evidence that the state is in fact complicit is not actually very strong. For example, the mere fact that immigration enforcement is never perfect is not evidence of “encouragement,” given that there are moral constraints on how far the state can go to enforce immigration laws.

Finally, Carens contrasts his claim that long permanence in a place gives a person membership rights with the idea that states are to protect the human rights of all persons within their territories. Since irregular migrants, because of their vulnerability to deportation, are often wary of asserting these human rights, Carens argues that there ought to be a sort of “firewall between immigration and the protection of migrants' legal rights” (33), so that even migrants who do not meet the threshold for amnesty can still gain legal protection against violence and access essential services like primary education or emergency healthcare.

Carens characterizes his argument as “an attempt to engage in a respectful conversation with people who believe deeply in the state's right to control admissions” (36) even though he himself believes in open borders. Yet this self-characterization invites the worry that Carens is actually engaged in a more radical project, and that his intervention into the (American) immigration debate is ultimately strategic. Presumably Carens thinks that the belief in the state's “right to control admissions” is too deeply entrenched to be easily challenged, whereas beliefs about “social membership” are not; but this is not itself a reason to respect the former belief from a theoretical perspective. At any rate, we would need to understand better why we should respect those who believe deeply in the state's right to control admissions, as opposed to, say, those who believe deeply in the essentially “Anglo” character of American culture.

More generally, there is something deeply unsatisfying about the sorts of moral rhetoric that both Carens and many of the other contributors to the book deploy. This “moral rhetoric” attempts to persuade an imagined citizenry, whose good faith is taken for granted, on the basis of appeals to certain widely shared intuitions (in particular, the intuition that long residence gives one a claim to membership), reinforced with vivid stories. But the real citizenry is often more refractory than these arguments imagine; they are not easily swayed by appeals to a single moral intuition, however clear and well reinforced by affecting stories. One would have wished for a deeper reflection on the purposes and limits of moral argument in democratic societies from the contributors to this work.

There is also something vaguely parochial about the book, even though Carens argues that his arguments are supposed to apply to liberal democracies in general; the volume has the strong flavor of an intervention into US political debates, with only minimal reference to the situation of other places and countries. (All the contributors work in American or Canadian institutions, and all appear to be deeply informed about American law.) This presents a tension between the apparent generality of the moral arguments deployed by Carens and the apparent “provincialism” of the examples. The concrete examples are highly affecting, but they are also “easy” cases, and the legal discussions are too closely tied to American and British particulars to be easily applicable to other liberal democracies.

The responses to Carens's argument vary, though most are sympathetic, and it is a strength of the book that one can read both author and critics together. Nevertheless, none of the responses really challenge Carens's theoretical framework; the closest to a challenge we find is Carol M. Swain's (relatively weak) argument that there are citizens in the US who are harmed by the actions of illegal migrants, in particular minorities and other underprivileged groups. She thus counterposes a different intuition about “fairness” to Carens's own, but without fundamentally contesting the essential role of fairness in this debate. And none of the contributors take utilitarian ethical positions, for example, that might consider the claims of the very poorest in the world to be more important than the claims of relatively wealthy migrants from middle-income countries, even if they have been settled for a long time in the country.

In general, this slim and well-produced book makes a thoughtful intervention into debates about the status of long-term “irregular” migrants, especially in the US. Its arguments are sober and well reasoned, though whether they will have much of a real political impact is perhaps doubtful.