I. Origins of Biological Sex and Sex Assigned At Birth
A. Sex in Midcentury Medicine
An excellent summary of section I:
For much of the twentieth century, many people subscribed to a simple model of the biology of sex that posited that every person has a male or female sex dictated by their genetics at birth; that those genes determine the hormones produced by an individual’s body; and that those hormones cause men’s and women’s physical and behavioral differences. Deviations from this model were seen as disorders of the physical or mental varieties. The term “biological sex” began appearing in U.S. legal authorities in the 1970s, reflecting the theories of midcentury psychologists who regarded transgender identity as a mental illness caused by early childhood influences, as well as the concerns of jurists about the need for a legal definition of sex that would preclude, for example, same-sex marriage. The term “sex assigned at birth” arose in the 1950s in the context of medical treatment of infants with intersex variations. In the 1990s, transgender rights advocates and activists reappropriated the term to craft a more inclusive definition of their community, and it began circulating in legal sources, such as statutes and judicial opinions, in the 2000s. “Sex assigned at birth” is now commonly used in judicial opinions, often in competition with “biological sex.” (pgs. 1833-1833)
By the mid-twentieth century, developments in genetics contributed to popular understanding as sex originating in the X and Y chromosomes, with the “master switch” theory that embryos are female by default but that a gene on the Y chromosome triggers the development of testes which in turn causes sex differentiation of body and mind via hormones. This understanding is outdated, with biology of sex/gender as more akin to a complex network. (pgs. 1833-1834)
The term “sex reassignment” appeared in the 1960s to describe surgical procedures for transgender patients and appears to have been borrowed from intersex treatment. This use of language may have been part of larger debate about whether transgender identity was a type of intersex variation requiring surgical intervention or a psychological malady from early childhood experiences. (pg. 1836)
Doctors advocating for sex reassignment surgery in the 1960s distinguished “sex assignment at birth” from other definitions of sex, such as psychological sex, social sex, sex of rearing, anatomical sex, and legal sex. (pg. 1837)
Psychoanalyst Robert Stoller coined the term “gender identity” in 1964 to describe psychological sex. (pg. 1837)
In 1965, a NY City Board of Health convened a committee of medical experts that denied updates to legal sex by male-to-female transsexuals and cited concerns regarding same-sex marriage, the all-male draft, and benefit programs available only to women. (pgs. 1837-1838)
B. Legal Understandings of Sex, 1970s to 1990s
Prior to 1970, U.S. legal authorities generally referred to “sex” simpliciter, not distinguishing between biological, social, legal, or other meanings. This reflected common understanding of “sex” encompassing questions of gender or sexuality.
In law, “gender” was used to refer to grammar or as a sexually sanitized synonym for sex.
Corbett v. Corbett (1979) was an influential English legal case adjudicating on whether April Ashley, a transgender woman, was a woman for purposes of marriage to a man. She argued that her psychological sex was female and so should be recognized as intersex and assigned female. However, the court was not persuaded due to expert testimony that transsexualism was a psychological disorder after birth. The Corbett court concluded that biological sex is fixed at birth and Ashley had “confused sex with gender.” (pgs. 1839-1840)
The term “biological sex” began trickling into U.S. case law in the 1970s, almost exclusively in cases involving transgender rights. Courts continued using “biological sex” in the 1980s almost exclusively in debates over LGBTQ rights. (pgs. 1840-1841)
“Biological sex” began appearing in 1980s army regulation on the exclusion of LGB people from military service. (p. 1840)
In the 1980s, the medical community increasing used “assigned sex” to replace anatomical sex in discussion of transgender patients. In 1987, the DSM III was revised to define gender identity disorders as “an incongruence between assigned sex […] and gender identity,” replacing the term “anatomic sex.” (p. 1841)
In the 1990s, transgender theorists reappropriated the concept of sex assignment in an effort to define their community. The term transgender emerges from grassroots organizing and was “[c]rafted to resist the imposition of labels created by the psychiatric establishment to define and contain cross-gender identities and behaviors.” (p. 1842)
Virginia Price is sometimes credited with coining transgender in the 1970s and defined it as “somebody who lives full time in the gender opposite to their anatomy,” as opposed to a transsexual, a person who has medically altered their anatomy. (p. 1842)
Transgender theorists defined transgender people as moving across a socially imposed boundary away from an unchosen starting place. (p. 1843)
Courts in the 1990s began referring to “biological sex” with increasing regularity. (Perhaps out of reliance on older versions of the DSM.)
C. Assigned Versus Biological Sex, 2000 to the Present
In the early 2000s, transgender rights advocates and legal scholars advanced a shift toward the language of assigned sex rather than references to anatomy, biology, or other aspects of the body. (p. 1844)
The 2013 DSM V used the term “natal sex” but it appears infrequently in case law. (pg. 1845)
After the 2014 transgender “tipping point,” references to assigned sex began to proliferate in case law. (p. 1845)
The term “biological sex” had appeared infrequently in biomedical research prior to the 2010s, but its usage increased over the course of that decade.
A search of the PubMed.gov database on September 21, 2022 for the term “biological sex” revealed 13 or fewer results per year until 2009, between 23 and 54 results from 2009 through 2015, 71 results in 2016, 80 results in 2017, 125 results in 2018, 142 results in 2019, and 225 results in 2020. (p. 1846)
The trend of using “biological sex” and has increased with laws enacted beginning in 2020. Most of them neglect to define “biological sex” or determine it based on original birth certificate, with no reference to any aspect of biology. (p. 1849)
II. The Case for Sex Assigned at Birth
This Part outlines the theoretical advantages of the concept of sex assigned at birth and explains how these advantages have played out in legal debates. (p.1850)
Advocates introduce “sex assigned at birth” for other explanatory purposes, such as to define what it means to be transgender and in discussions of background facts about transgender identity, often with expert testimony. This debate is not about terms; it is about how courts should conceptualize sex and gender as complicated, intertwined, and multifaceted phenomena. Sex assigned at birth is a concept that does important descriptive and normative work in legal disputes. It challenges premises that are central to opposition to transgender rights: the explicit premise that biological sex provides a neutral and objective basis for rules intended to exclude transgender people, and the implicit one that transgender identity is not “real” because it is inconsistent with biological sex. Additionally, sex assigned at birth invokes concerns about autonomy and equality by appealing to the injustice of assignments of identities that dictate an individual’s rights, privileges, and obligations. And it resonates with the argument that information about a person’s genitalia at birth is personal health data, not a matter that should be made public in ways that are offensive to individual dignity. These advantages support the case for introducing the idea that sex is assigned at birth rather than assuming sex is “biological,” “natal,” or “identified at birth.” (p.1851)
A. Challenging “Biological Sex”
Opponents of transgender rights often rest their arguments on the assumption that “biological sex” is a simple, static, binary, self-evident characteristic that does not encompass “gender,” which is a social, psychological, or even ideological phenomenon. They frame controversies as contests between science and culture, portraying themselves as standing for biology, nature, and truth, and the other side “as hectoring from a postmodern gender La La Land.” (p. 1851)
The Anti-Trans Crowd's Central Argument: Biological Sex is Objective & Nondiscriminatory
Anti-trans crowd argues that “biological sex” is a neutral and nondiscriminatory basis for excluding transgender students, since it does not classify on the basis of transgender status or prohibit based on social stereotypes (i.e. gender). (p. 1851-1852)
“Defendants and the United States suggest the Act does not discriminate against transgender individuals because it does not expressly use the term ‘transgender’ and because the Act does not ban athletes on the basis of transgender status, but rather on the basis of the innate physiological advantages males generally have over females.” (p. 1852)
Pryor, C.J., dissenting: “The policy does not turn on how students ‘act and identify.’ It assigns bathrooms by sex, which is not a stereotype.” (p. 1852)
Sex assigned at birth challenges the view that the sex classification on a birth certificate equates with some unified concept of “biological sex.” It points to the fact that the biology of sex is complex, multifaceted, and dynamic, and the process of assigning sexes to infants is a social one. It opens space for the argument that rather than being purely social, gender identity is, for many individuals, at least partly a result of biological processes. (p. 1853)