A key tenet of business and human rights has become the introduction of mandatory human rights due diligence (HRDD), a process that attempts to introduce the essentials of due diligence into domestic law by means of incentives and legal requirements for companies.  On the tenth anniversary of the UN Guiding Principles on Business and Human Rights (UNGPs) the Working Group on Business and Human Rights (WGBHR) stressed that the “hardening” of the UNGPs by means of mandatory HRDD was “one of the most remarkable developments of the last ten years”. The WGBHR has advised on the complexities, policy trade-offs and nuances when this takes place. And with the forthcoming transposition of the EU Corporate Sustainability Due Diligence Directive (CSDDD) this process is meant to increase. However, the conceptual basis of this soft-to-hard law translation is largely unrevised. For instance for the UNGPs, the corporate responsibility to respect human rights was based on “the basic expectation society has of business in relation to human rights” and not on law or principle. Now that legislatures prepare HRDD laws, should they rely on expectations as well?

The UNGPs refer to human rights in two rather different ways: as applicable law and as the content of “global standard of expected conduct” (see UNGP 23(a), the difference between “comply” with applicable laws and “respect”). To lean on expectations (soft law) instead of consent (hard law) afforded the UNGPs an unrestrained application. Accordingly, the UNGPs address corporations irrespective of size (UNGP 14), place of operation, time, and most importantly, irrespective of the law where they operate.

For the UNGPs, businesses’ responsibility is justified on social expectation,  and the referral to the international bill of rights (in UNGP 12) is rooted in their use as “benchmarks against which other social actors judge the human rights impacts of companies”  (A/HRC/8/5, para. 58, similarly A/HRC/11/13, para 53). That expectation was preferred over other justifications, was partly due to the policy nature of the mandate, but also due to the goal of the project not to create new international legal obligations, and instead provide guidance and elaborate on the implications of existing standards (A/HRC/23/32/Add.2, para. 2). But what happens when HRDD gets translated into actual domestic law? Does the concept of a “global standard of expected conduct” remain necessary or should other legal justifications take its place?

The concept of “global standard of expected conduct” (UNGP 11) has the merits of avoiding the debate of the recognition of TNCs as having international legal personality A/HRC/4/35/Add.2, para. 11). More importantly, it avoids narrowing HRDD only for the rights protected by the home or host State (A/HRC/11/13, para. 46). But if translated into domestic law, it might miss the opportunity of asserting that such responsibility stems not from the expectations of society but from the nature of human rights themselves.

There are many legal alternatives to the use of social expectations. To provide two examples, it could be said that rights recognized but not created by treaties create a correlative obligation, chiefly but not exclusively for other actors, like States or corporations (to use Hohfeld’s structure, YLJ, 1913). Or that, similarly, there is a correspondence between treaty obligations and human rights. In other words, those human rights would have certain subsequent implications following the logic of the benefit theory of rights (see e.g. Hart, 1982, p. 172). In both cases, mandatory HRDD would be grounded on human rights themselves, and not on what society expects, which ultimately can change over time. Moreover, the idea of rights and correlative obligations (for corporations) would avoid the debate of the personality of corporations under international law, precisely because the rationale would operate in domestic law where corporations’ personality is uncontested.

It is largely understandable that the SRSG was trying to avoid the mistakes reflected in its immediate successor (the Norms on Transnational Corporations) that justified its mandate (A/HRC/17/31, para. 2). The concept of standard of expected conduct seemed a good alternative for problematic legal justifications of the corporate responsibility to respect human rights. However, now that domestic legislatures introduce mandatory HRDD laws (as the transposition of the CSDDD, Article 37), that problem disappears and there is room to explore alternatives, such as HRDD stemming not from social expectations but from human rights themselves. Legislators will have to decide whether to endorse the rationale of the UNGPs or to fit it with other legal justifications when passing mandatory HRDD laws.