Vol. 25 No. 6 (June 2015) pp. 89-92

THE LIBERTY OF NON-CITIZENS: INDEFINITE DETENTION IN COMMONWEALTH COUNTRIES by Rayner Thwaites. Oxford and Portland: Hart Publishing. 2014. 325pp. ISBN: 9781849464314.

Reviewed by Rebecca Hamlin, Legal Studies Program, Department of Political Science, University of Massachusetts, Amherst. Email:

The field of comparative constitutionalism is in an exciting place, as increasing numbers of scholars apply the comparative method to the study of constitutional law and courts. Yet there is still much work to be done to understand the precise ways in which a comparison of high court decisions can illuminate larger-scale political developments. In other words, because it is still in its early stages as a field, comparative constitutionalism often has more momentum than methodology. Rayner Thwaites’ recent book, THE LIBERTY OF NON-CITIZENS: INDEFINITE DETENTION IN COMMONWEALTH COUNTRIES, perfectly exemplifies the importance of comparative constitutional law, and the promising but unsettled state of the comparative constitutionalist project.

The topic of THE LIBERTY OF NON-CITIZENS is fascinating: when a person is deportable, yet cannot be deported, what is to become of them? Deportation and removal is an almost routine aspect of border control for liberal democracies, but there are many scenarios that can complicate and delay deportation. For example, if a non-citizen’s country of origin no longer exists, or they are stateless, there is no country to which deportation can be made. Similarly, if a non-citizen’s birthplace refuses to accept them due to their criminal record, or declares that they will be tortured if they are returned, the host country can be equally stymied in its attempts to deport. In these situations, policy-makers and judges have wrestled with the question of whether non-citizens can be detained indefinitely in lieu of deportation, essentially condemning them to a life sentence, or whether they must be released back into the unwilling host country.

High courts in many liberal democracies have addressed this question, leading to what Thwaites calls “some of the key public law decisions of the past decade” (p. 10). Further, high courts have resolved the question in a variety of ways, ranging from a broad allowance of indefinite detention in Australia, to a theoretical endorsement in extreme circumstances in Canada, to a prohibition through an assertion of judicial authority in the UK. Thus, Thwaites sets up an interesting puzzle; why have similar liberal democracies, all commonwealth countries, reached very different answers to the question of whether indefinite detention of non-citizens is allowable under law? In order to solve this puzzle, he engages in extensive analysis of the key decisions in each of those three countries, and the precedent upon which they are based. Thwaites also pays substantial attention to the United States Supreme Court case ZADVYDAS V. DAVIS, in which a majority of the Court found indefinite detention to be unconstitutional, though this remains a shadow case without the same level of analysis.

Thwaites proposes a provocative answer to his important and interesting puzzle. He concludes that the cross-national variation in high court decisions regarding indefinite detention stems from judicial attitudes about non-citizens’ rights, rather than from [*89] constitutional differences or “any difference in legal structure” (p. 306). He claims that judicial approaches to indefinite detention cases take two forms. Judges are either rights-protecting, with a substantive approach based on the post-WWII “human rights project” (p. 19), or, they are rights-precluding, which is a positivist approach based on an emphasis on classification and status. Rights-protecting judges are willing to limit executive power and find indefinite detention to be unconstitutional whereas rights-precluding judges are willing to defer to the executive and allow it.

While I found THE LIBERTY OF NON-CITIZENS deeply engaging and thought-provoking, I was not convinced by Thwaites’ conclusion about the centrality of judicial outlook for explaining cross-national variation. Put simply, the book would have been improved by a more thorough treatment of alternative explanations, such as the importance of text, or the characteristics of the non-citizens themselves. First, it is essential for the puzzle Thwaites outlines, and for the purposes of a controlled comparison, that his three countries be considered “most similar systems” (Mill 1843, Przeworski and Teune 1970). Because they are commonwealth countries and liberal democracies, he argues, both the rights-protecting and rights-precluding interpretations are equally available to judges in all the countries he studies.

But there are problems with this characterization. Australia, Canada, and the United Kingdom do not just vary on the outcome in which Thwaites is concerned: indefinite detention decisions. They also vary in terms of the constitutional entrenchment of individual rights. Further, all of the states in which high courts put limits on detention have some kind of enumerated right to liberty. In CHARKAOUI V. CANADA, the Canadian Supreme Court relied on Section 7 of the Charter of Rights and Freedoms to find such limits. In A AND OTHERS V. SECRETARY OF STATE FOR THE HOME DEPARTMENT (2004) UKHL 56, the British House of Lords applied the European Convention on Human Rights Article 5 right to liberty, which they are empowered to do under the 1998 Human Rights Act. Similarly, in the American ZADVYDAS case, the majority applied the 14th amendment right to due process. By contrast, in Australia, which does not have enumerated individual rights in its Constitution, the Supreme Court found that indefinite detention of non-citizens was allowable. In AL-KATEB V. GODWIN, Chief Justice Gleeson explicitly stated that even though the outcome was “tragic,” without a bill of rights or constitutional amendment, there was nothing the Court could do. Especially given that the decisions Thwaites examines are not all unanimous, it is clear that constitutional text does not completely determine how judges behave. However, by insisting that his country cases are most similar, he downplays the significance of constitutional entry points to a degree I found unconvincing.

Thwaites’ characterization of judicial approaches as either rights-protecting or rights-precluding is also unsatisfying because it turns a continuum into a binary. His categories suggest that there are two ways to conceptualize the liberty of non-citizens, but both the statutory and jurisprudential treatment of non-citizens in the countries he examines make clear that the rights of non-citizens can depend on aliens’ length of stay, the roots they have established in the host country, their legal status prior to being found deportable, their country of origin, and many other factors. [*90] Indeed, the aliens in the cases he analyzes varied widely on those sorts of dimensions, and the opinions in their cases represent a range of nuanced responses to the question of indefinite detention, not a simple yes or no. In many cases, the reasoning of the judges seems less about their view of the rights that should be afforded to a generic non-citizen, and much more focused on the specific type of non-citizen before them.

THE LIBERTY OF NON-CITIZENS could also have done more to situate the court decisions it discusses in their larger political and strategic contexts, particularly the global influence of the War on Terror. For example, the Canadian CHARKAOUI case, which involved an immigrant suspected of involvement in terrorist activities, was heard before September 11th 2001, but decided in the fall of 2001, which helps to explain its national security framing. (For a discussion of the larger political context surrounding the CHARKAOUI decision, see Macklin 2009.) Further, the book does not acknowledge that the ultimate outcomes for non-citizens have not varied as much as the cases alone would suggest. In fact, in all four countries Thwaites discusses, the parties to the indefinite detention cases are no longer being held and indefinite detention is not currently being practiced, though immigration detention and other restrictive policies continue to be widely used. After the High Court of Australia found that Al-Kateb could be detained indefinitely, the immigration Minister granted him a discretionary visa and he was allowed to leave detention. Similarly, although the Canadian Supreme Court found that indefinite detention was theoretically justifiable in some cases, the parties to the CHARKAOUI case were all released. In the aftermath of the detention decision in the UK, parliament passed the Prevention of Terrorism Act of 2005, which created “Control Orders,” controversial restrictions of people’s movement and association. Thwaites concludes that the so-called BELMARSH decision, as liberal as it was, has not improved the status of non-citizens’ rights in the UK because the indefinite detention regime has been replaced by “an increasing armory of other measures directed at the removal and exclusion of non-citizens” (p. 214). Because THE LIBERTY OF NON-CITIZENS focuses almost exclusively on judicial behavior, this evidence in support of cross-national policy convergence around national security concerns goes unexplored in the book.

Another contextual element that is mentioned, but under-explored in the book is the question of “cross-fertilization” (Slaughter 2004) or “borrowing” (Jacobsohn 2004) across jurisdictions. Not only are there clear parallels in the policy being made in each place, judges in the U.K, Canada, and Australia reference each other and the relevant American case law quite frequently. Thwaites does note these references, but I would have liked to see a more systematic taxonomy of judicial borrowing on this topic. In my work comparing asylum law in the United States, Canada, and Australia, I conclude that borrowing is “a strategic tool, rather than a nuanced review of international jurisprudence” (Hamlin 2014, 142). It is often used to add legitimacy to a decision when a court is going against the legislature. In particular, commonwealth countries cite UK decisions for this reason. But courts also sometimes cite foreign dissents, and even cite cases in order to disagree with them. Thwaites’ project was well-suited to a more thorough engagement with the circumstances under which courts choose to look to each other for guidance about detention. [*91]

Studying similar high court cases on the same topic cross-nationally can be extremely tempting, especially when the topic of the common decisions is so significant. However, this kind of work can also become a trap unless one situates the decisions in their larger strategic political context. THE LIBERTY OF NON-CITIZENS is an important contribution to the study of immigration law in each of the three jurisdictions that Thwaites analyses. However, because it leaves so many questions about the relationship between law and politics unanswered, it misses some exciting opportunities for advancing the field of comparative constitutional law.



Jacobsohn, Gary. 2004. “Borrowing: The Permeability of Constitutional Borders.” TEXAS LAW REVIEW 82: 1763-1818.

Macklin, Audrey. 2009. Asylum and the Rule of Law in Canada: Hearing the other (side). In REFUGEES, ASYLUM SEEKERS AND THE RULE OF LAW: COMPARATIVE PERSPECTIVES, ed. S. Kneebone, 78–121. Cambridge, UK: Cambridge University Press.

Mill, J. S. [1843]. 2002. A SYSTEM OF LOGIC. Honolulu, HI: University Press of the Pacific.

Przeworski, A., and H. Teune. 1970. THE LOGIC OF COMPARATIVE SOCIAL INQUIRY. New York: Wiley.

Slaughter, Anne-Marie. 2004. A NEW WORLD ORDER. Princeton: NJ. Princeton University Press.



AL-KATEB V. GODWIN, HCA 37 (2004).


ZADVYDAS V. DAVIS, 533 U.S. 678 (2001).

© Copyright 2015 by the author, Rebecca Hamlin.