Proportionality: Constitutional Rights and their Limitations, written by former President of the Israeli Supreme Court, Justice Aharon Barak, is the most comprehensive and authoritative account of the vast literature on proportionality, and would be indispensable to anyone interested in the field. Barak evaluates in his book several justifications for the use of proportionality and several defenses of proportionality against its critics. In this review article we concentrate on one such defense, which has gained prominence in recent years and on which we have written also in the past: viewing proportionality as a structured and analytically coherent set of tests requiring the government to provide reasons and justifications for all of its actions.
We identify several prominent recent writers and Barak among them that represent a shift in the literature on proportionality towards a justification-based approach. We assess four strong rationales for the duty of the government to give justifications and provide reasons for its actions: it shows an attitude of respect towards the citizens affected by governmental actions; it is essential to the legitimacy of governmental authority; it facilitates democratic deliberation and participation, and it furthers governmental accountability and trust between the citizens and the government.
However, we claim, those rationales do not necessarily support proportionality. Indeed, those writers who support the justification-based approach disregard the fact that proportionality is not the only method to promote justification nor even the best one. We argue that a more categorical approach, such as “exclusionary reasons”, follows just as much from the ideas underlying justification. Therefore, in order to be justified, proportionality needs another anchor than the justification-based approach, and attempts to “save” proportionality by relying on the idea of justification are problematic.