In the 21century, sustainability is emerging as a new “constitutional key concept” which, like sovereignty, democracy, rule of law, equality or freedoms, demands attention by constitutional scholars: it, too, needs to be interpreted, balanced, and enforced. Out of the 193 UN Member States, 67 constitutions use the words “sustainability” or “sustainable” (Groppi 2016, 2022). All of these references are found in the constitutions adopted or amended after 1987, when Brundtland Commission’s report, “Our Common Future”, defined “sustainable development” as “development that meets the needs of the present without compromising the needs of future generations”. Actually, sustainability clauses have been introduced in constitutions under the influence of international instruments (most of them soft law) (Sands and Peel, 2012; Touzet, 2008).
Scholars pointed out (Bosselman, 2008) that sustainability has a close link with the future, more particularly with intergenerational responsibility. In the vast majority of cases the references concern the protection of the environment or of natural resources (Boyd 2012), and in some cases to address climate change and food sustainability, to preserve those goods for the sake of future generations: a necessity which is becoming especially evident as far as climate change and food crisis are concerned. As for the “geographical” perspective, the expression is found in all regions of the world. However, it finds a particularly large place in Latin-American constitutions: the constitutions of Bolivia, Ecuador and Venezuela contain countless provisions on sustainability and sustainable development, including economic and financial aspects, according to a regional trend aimed at tackling environmental issues at the constitutional level (see also Brazil (1988) and Colombia (1991)). Almost all those provisions, with few exceptions, are substantive provisions of programmatic nature, which require the active intervention of public authorities. Procedural provisions are almost absent. The only examples of procedural rules in terms of sustainability are those on participatory democracy in environmental matters (Ecuador, art. 398), or on consultative bodies (Burundi, art. 280 Gabon, art. 103; Guinea, art. 138; Ecuador, art. 156; Morocco, art. 152), according to the French model of the “Economic, Social and Environmental Council” (art. 69 of the French Constitution). One constitution mentions the need for a parliamentary committee (Guyana, art. 119B). Only the Hungarian Constitution of 2011, entrusts this task to the “Ombudsman of fundamental rights” (art. 30).
The “sustainability clauses” are formulated in such general terms that they raise important questions as to their effectiveness. Actually, the democratic decision-making process does not seem to be the right forum to adequately take into account sustainability needs, due to its short-term perspective, linked to the electoral process necessities and timing (scholars consider this as the “democratic dilemma”: Dobson 1996; Eckersley 2004). In the (very likely) case of an insufficient legislative implementation, the question thus arises as to the direct applicability by judges (e.g. for the purposes of compensation, to claim responsibility for the non-execution by public authorities). However, even if these clauses were not considered as self-executing and if we qualify them as standards for judicial review, it would be very difficult for constitutional judges to declare the unconstitutionality of the inactivity of the legislator. Moreover, in very technical matters, as those of environmental sustainability, they would be asked to deal with many scientific issues, that are very difficult for lawyers to decide, without the support of non-lawyer experts. Very often, constitutional judges lack of procedural tools aimed at knowing scientific facts and data. Not to mention the likelihood that, faced with such “open” and generic clauses, the least active constitutional judges may give up guaranteeing sustainability needs, opting instead for solutions aimed at avoiding the challenges, by favoring, more or less openly, the discretion of the legislator (it is what happened in Norway).
We are therefore faced with a difficult dilemma: on the one hand, as we said, the democratic decision-making process does not seem to be the right forum to adequately consider the needs of sustainability. On the other hand, the constitutional clauses, in their vagueness and genericity, entrust an excessively difficult task to the judges, called upon to strike a difficult balance. The question is therefore if a more appropriate institutional design, as for the governance models, can be imagined, so that law and policies could more effectively contribute to a better guarantee of sustainability.