Some laws and the social conditions they affect seem relatively easy to change. When the pandemic started in 2020, the Australian government doubled the unemployment benefit with little discussion and no opposition. Poverty was drastically reduced. But the change was temporary. In 2021, the benefit dropped nearly to its previous level, and the rate of poverty increased again. Some commentators noted that poverty—often presented as a hard problem of governance—was actually not really that difficult to address (though there are, of course, adjacent social issues and flow-on effects). Other laws and associated social conditions are much more difficult and perhaps impossible to change. Private property is part of the fabric of social life in capitalist societies. Changes to the law of property, however important they are for challenging problems such as inequality, ongoing colonialism, and ecocide, are always highly contestable, difficult to imagine, and rarely made.

The topic of this special issue is decertification of sex/gender: abolition of the requirement that a legal sex or gender must be stated on certificates issued to the parents of a new-born baby or to an adult wishing to establish their identity for bureaucratic purposes. Decertification would unsettle hegemonic definitions of sex/gender and require consequential changes to laws and policies that assume formal sex status. Decertification seems to be at once an incredibly simple and an almost impossible project for legal change.

Reduced to the essence and purpose of birth registration and certification, decertification of sex/gender would appear to be a straightforward reform. The generally accepted minimal purpose of birth registration under present legal conditions is to record the existence of a living child or, alternatively, to record that a pregnancy ended with a stillbirth. The fact of existence, of being born, is officially registered so that the child or their parents can, now or in the future, with a certificate issued by the registrar, establish their age, their place of birth and parentage, and potentially their citizenship.Footnote 1 Once registered and certified, bare existence becomes legal identity and the fact of birth is invested with normative significance. A proper name is attached to a new being. Without registration, a human being may exist legally, but will be less visible to law, lack an official name and the means of identification, and may therefore experience difficulties establishing who they are before the law. Their legal subjectivity will be in doubt. Lack of birth registration remains a problem faced by many Indigenous Australians in their engagements with the imposed legal system (Castan et al. 2011). But neither sex/gender nor the status-rights that once flowed from it are fixed at birth. In many contemporary Anglophone states, sex/gender no longer determines fundamental legal status in the way that it once did. Legal incapacities that once attached to women from birth have been lifted: we can get married and own property, we can vote, we can hold public office, and so forth. Male incapacities, where they have existed, have also been removed—in many countries, like women, men can marry each other. We can, with varying degrees of difficulty and depending on the legal jurisdiction we find ourselves in, change our sex/gender. The capacities and incapacities of different groups of people that still exist are, for the most part, no longer indelibly attached to birth identity but are defined by legislation. As an administrative process, registration is necessary to record legal existence, and the registration of an apparent birth sex may or may not be an important part of that process. The issuing of a birth certificate is also necessary to establish the legal identity of a human being, but it is not necessary for legal purposes that the certificate identifies a person as having a sex/gender.

Experiences that reveal the inadequacy of the male–female binary traditionally available for registration are leading to legislative multiplication of sex/gender options in the registration and certification processes. ‘Male’ and ‘female’ are no longer the only options in some parts of the world (see Moulds 2019). In South Australia where I live, ‘sex’ (presumably male or female) is registered if determined and may later be changed to recognised types of ‘sex or gender identity’. These recognised identities are “male”, “female”, “non-binary”, and “indeterminate/intersex/unspecified”.Footnote 2 Such options are a closed and mutually exclusive list; they prevent self-identification with a category that is not listed or with multiple categories. Instead of multiplying categories with an unsatisfactory list, it would be possible to eliminate compulsory certification of sex/gender. Not everything on the register needs to appear on a birth certificate, and some information is intentionally withheld. Decertification of sex/gender is not in itself a radical reform. People would still (presumably) mostly accept normalised social designations or alternatively identify in a non-hegemonic fashion. Apparent birth sex could still form part of the historical record alongside other extensive data collected about births, such as birth weight, length of pregnancy, and existence of gamete donors, but it would be accorded no essentialised legal significance. Birth certificates would be silent on the question of sex/gender, given that—like race, religion, (dis)ability, class—it no longer has a necessary legal meaning.

From this point of view, decertification seems quite straightforward and defensible—the removal of a legal remnant which, however, may not necessarily have much wider impact (see Grabham 2023; Renz 2023). Just as the lifting of incapacities of women was only the beginning of more substantive social change that is still ongoing (every step hard-fought and improvements often fragile) removal of the legal certification of sex/gender will clearly not produce fundamental change, especially not in the short term. The social categories of sex/gender would still exist and would still be contestable (and contested) in a variety of spaces. Sex/gender-based inequality and exploitation would still exist and—like racial and religious inequality—would attract legislative mechanisms to address it, though some of these may need modification (Grabham 2023). Sex- and gender-diverse people would not be forced to establish their identity using a certificate that conflicts with their persona (Kelly and Robert 2018).

As this special issue shows, however, decertification cannot be so easily reduced to the bare essences and purposes of birth registration. It would clearly necessitate change to other laws that rely on sex/gender identity or which use gendered terms. Many other vectors of complexity beyond changes to doctrinal law are considered extensively in the preceding articles, but I will comment on only a few issues—the entanglement of law with social and symbolic norms, the biosocial character of sex/gender, and the temporalities of legal change.

First, sex/gender is clearly not only a legal formality of little structural significance. This is in part because ‘law’ is never only ‘law’. There can be no straightforward legislative change without an extensive infrastructure of formal laws and procedures to contextualise and enable the change. That infrastructure, together with all of the doctrine it produces, is reliant on and ultimately blended into an extended field of social norms in their complexity, materiality, and plurality (see also Ewick and Silbey 1998; Davies 2017; Emerton 2023; Peel and Newman 2023). Formal law is only a thin slice of an extensive interwoven normative universe, official and unofficial (Cooper 2023). No single part of this nomos exists by itself, though it is frequently divided for analytical purposes into social-institutional ‘systems' such as the economy, religion, education, law, the class system, the gender system, and so forth. Such divisions can be helpful but are not unassailable. Some of the meanings established or recognised by formal law are more woven into social life than others. The exact level of the unemployment benefit is not particularly integrated into fundamental social structures. But, like property, sex/gender is—or is felt to be—a fundamental, though increasingly controversial, defining attribute of contemporary social life. Sex/gender is therefore not only a legal addition to or intervention in social life, but part of our socio-cultural background (cf. Hekman 1999)—like individualism, like property, like white privilege, it is the air we breathe. The multiple meanings of sex and gender saturate culture, especially, but not exclusively, in the sphere of human identity and our own personal need to identify. At present, therefore, and as demonstrated by many of the survey responses gathered in the ‘Future of Legal Gender’ project, decertification is illegible to many people—it simply does not make sense as a proposal (Emerton 2023; Peel and Newman 2023). The ability to change sex/gender makes sense, and the multiplication of possible identities makes sense, because these reforms are based on adding to what already exists. But it is perhaps more difficult to imagine total removal of what is often regarded as a fundamental and natural classification.

This general attachment to sex/gender is ingrained and taken for granted as a structuring force of social life. The deeply felt need that many (not all) people have to identify themselves and others through the lens of sex/gender appears to take on a special force insofar as legal registration is concerned because of the symbolic and ritualistic aspects of being registered or certified: “both the birth registration process and the resulting certificate carry practical and symbolic weight” (Clapton 2014, 211). The formality and apparent solidity of a legal documentary and historical record forms an inalienable link between the individual and their identity, that is to say their legitimacy in the world. For many, this place includes their sexed/gendered identity, and points to a truth that might otherwise be unavailable.

Sex/gender is therefore not only legally inscribed, but emergent from and interwoven with socio-cultural and political norms and expectations. But, second, sex/gender also does not only exist in the social space beyond law: it is a biosocial and biocultural lived experience of animal bodies and part of a complex emergent reality. Sex and gender have often been separated by feminists and others wishing to differentiate the underlying biological form of the body from the meanings imposed by society and adopted by gendered persons. The differentiation of biology from culture has in many respects been a clarifying discourse: it promotes understanding of the contingency of many gender-related attributes, permits greater interchangeability of gendered roles, and lays bare options for contestation and critique of gender as a social system. The distinction of gender from sex has been an important strategy for denaturalising the socially imposed and performed differences between female and male because it uncouples the body from a pre-determined social identity. But it is also problematic in many respects because biology and culture cannot fundamentally be separated in this way. Sex itself is constituted taxonomically as a binary, in the process rendering invisible those whose bodies and/or lived experience do not fit. And as sexed bodies, persons orient or perform sex/gender in particular ways (Butler 1990; Ahmed 2006), repeating and reinventing circulating biosocial codes that are the still-evolving products of longstanding biological and social processes. In the here and now, orientation of the body—repetitive movements and the objects that may thereby be grasped—is, as Sara Ahmed argues normative (2006, 66). Social norms and laws are not separable from the body—sex and gender are concurrently emergent from practices, relationships, meanings, and symbols. The co-constitutive nature of sex and gender does not preclude that—at some times and in certain contexts—sex and gender can be understood and experienced as separate. It is in this space of undecidability between whether sex/gender is one or two, that so much controversy and disagreement within and beyond feminism arises. The undecidability is both personal and social, meaning that generalisation is difficult—everyone is entitled to wonder whether efforts at universalisation reflect their own experience. Perhaps a level of discomfort is inevitable about whether an abstraction can encapsulate a life. There can be no essence of sex or of gender in such a mobile and contestable space. That does not necessarily help untangle matters, however: a biosocial paradigm creates a situation where it is possible to think sex and gender separately, but constantly forces them together.

The third area I wish to comment on relates to the plural temporalities of legal change that are so strongly evoked in this special issue. The complexity of sex/gender in its socio-legal and biosocial landscapes is both good and bad news for law reform. Change—including change of the law—is inevitable but never uncomplicated. Even the most resistant socio-legal constructs will change over time. But will such changes represent ‘progress’, and how can feminists promote change that is helpful to the project of eliminating misogyny and all forms of sex/gender-related violence and inequality?

It is popular these days to speak of change in complex systems as ‘non-linear’—the term has its genesis in the study of thermodynamics and a broader application in complex systems theory (Prigogine 1997) but is applied in many contexts to denote change that emerges from inter-woven social, physical, biological, and/or ecological processes. Non-linearity refers to change that is uneven, cumulative and therefore historical; not determined by or reducible to prior conditions but always constrained by them; and characterised by multiple unpredictable feedback loops that amplify or negate transitions happening elsewhere. The physical reference point is not the billiard ball that follows a defined trajectory but a whirlpool or—more pertinently, and as this special issue illustrates so clearly—complex biosocial systems like sex/gender which layer inputs from different spatial and temporal scales, including evolution, recent history, diverse social practices, and imagined futures (cf. Walby 2007). Evolutionary theory may offer a comparable understanding of change that highlights the built-in and unpredictable movement of life towards the future rather than the interactions of multiple complex systems. In her reading of Darwin, Elizabeth Grosz (2004) comments on the unpredictable but always unfolding change theorised by evolution:

Darwin presents, in quite developed if not entirely explicit form, the germs for an account of futurity, the direction forward as the opening up, diversification, or bifurcation of the latencies of the present, which provide a kind of ballast for the induction of a future different but not detached from the past and present. The future emerges from the interplay of a repetition of cultural/biological factors and the emergence of new conditions of existence: it must be connected, genealogically related, to what currently exists, but is capable of a wide range of possible variation or development of current existence. A future predicated on repetition and emergence is variable, full of potential, but can it be directed? Can the inevitability of change and the openings left by complex orders be pushed in a particular direction?

The prefigurative thinking that underpins this special issue harnesses the complexity and historicity of change and turns it from analysis of potential emergence to a future-oriented politics (Cooper 2023). The research floats a reform proposal to test and socialise it, thereby intervening experimentally in the landscape under review. Prefiguration takes possible futures—that are imaginable but perhaps not dominant in the present—and deploys them as if they are present. The deliberate repetition or amplification of something that does not yet exist, but could, enlarges the space of the imaginable and unsettles the straight path into the future. It exploits the fact that legal change is never linear or straightforwardly ‘progressive’ toward some end point. Linear change is precluded by the relational complexity of the nomos and also—especially in the case of sex/gender—its biocultural/biosocial character. Any change is constrained by the possibilities set by past and present conditions, but might be provoked by proactive interventions such as this research.

Undoubtedly, particular reforms and their consequences cannot be determined—the trajectory of legal change will never be like that of a billiard ball. Perhaps, however, feminist experimentation and prefiguration can affect the probabilities associated with the emergence of foreshadowed change. “Thinking from the perspectives of women’s lives”, as explained decades ago by Sandra Harding (1991, 150), “makes strange what had appeared familiar”. Similarly, the perspective of sex- and gender-diverse people (and, to a lesser extent, those of us with other resistances to gender normality) makes strange the familiar binaries of sex/gender. Prefiguration, by contrast, inverts this by familiarising that which is unimaginable. The strangeness of decertification—of living without a legal gender—is made familiar and more probable by prefigurative strategies. Over time, such an approach may also alter the balance of simplicity–complexity, so that decertification can be seen as the uncomplicated reform that I believe it has the potential to be.