Proportionality is a legal principle that allows (or requires) balancing between competing values. This enables judges to decide whether a measure has gone beyond what is required to attain a legitimate goal and whether its claimed benefits exceed the costs. Originating most clearly in German 19th century administrative law, proportionality has become a standard feature of constitutional analysis: since the Second World War it has gradually spread worldwide. With the work of in particular Robert Alexy a common theoretical framework has become available. Yet at the same time the way in which proportionality is actually applied varies widely – not just between jurisdictions, but within them. For instance, instead of strict balancing between values a necessity test is often applied.
In his book, based on his PhD thesis at the Graduate Institute of Geneva, Benedikt Pirker claims that such differences can be explained by the institutional context of the balancing. Determining the nature of the test required is done by means of pre-balancing, an exercise looking at the particular situation of the reviewing tribunal. In his opening theoretical chapter Pirker argues that this in turn leads to the adoption of either of two models: (i) equal representation review; or (ii) special interest review. The essential difference is whether the values that are balanced are a priori deemed to be of comparable significance, in which case strict balancing is feasible, or whether one of the interests is from the outset held to be of preponderant value, in which case an alternative test like necessity becomes the judicial norm.
In his following chapters the author successively examines six jurisdictions: German and US constitutional law, the law of the European Court of Human Rights, European Union Law, WTO law and finally international investment law. Within each of these settings he reviews the main cases and distinguishes between the types of issue that determine the standard applied. For example in the case of the EU equal representation review applies to fundamental rights and citizenship, whereas special interest review applies regarding the internal market freedoms (where economic integration is the special interest at issue), as well as concerning fundamental rights in their horizontal dimension (with private autonomy as the special interest).
In doing so the book covers a wealth of material that is presented in a concise and disciplined manner and represents a true tour de force by the author. The pace is demanding and so is the argument, but well rewarding. As a comparative study it enriches the available literature on which comparativists and non-comparativists alike can draw. It also resolutely takes a global perspective.
I have only a few mild criticisms of this refreshing piece of scholarschip that may reflect my own shortcomings more than those of the author.
– In the first place I have not quite been convinced by the concept of pre-balancing. It is explained as necessary for the authorities (one would presume judges) to engage in so as to decide whether to apply proportionality and can then lead to either equal representation of special interest review. At the same time the binary outcome suggests little reflection would in fact be required. Moreover if judicial review is meaningful, within each of these two respective mutually exclusive scenarios a wide range of outcomes would presumably still be possible. In other words I have been convinced by the comparative side of the study, including the demonstration of the theoretical framework involved therein, but not (or perhaps not yet) by the prescriptive theoretical side.
– Second, in my view the study would have gained from fleshing out in greater detail some of the key cases with a more detailed treatment of the competing arguments in order to add not just colour to the text but also to allow a deeper understanding of the issues – at least for the reader. Now the presentation at times seemed rushed: a pity given the evident expertise of the author. But this more general comment is a question of style which is rightly personal.
My conclusion is that this book by Benedikt Pirker is a timely and important work which well deserves a wide readership among all those interested in legal theory, in comparative law as well as (perhaps closer to home for the readership of this blog), in EU law.
 Cf A. Stone Sweet and J. Mathews, “Proportionality Balancing and Global Constitutionalism”(2008) 47 Columbia Journal of Transnational Law 73.
 R. Alexy, A Theory of Constitutional Rights (translated by J. Rivers) (Oxford Univrsity Press, New York 2002).
 Cf W. Sauter, Proportionality in EU Law: A Balancing Act? TILEC Discussion Paper 2013/3 http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2208467
 Cf in the European context N. Emiliou, The Princple of Proportionality in European Law: A Comparative Study (Kluwer Law international, London/The Hague 1996); E. Ellis (ed), The Principle of proportionality in the Laws of Europe (Hart Publishing, Oxford 1999).