President Lyndon Johnson signs the Civil Rights Act on July 2, 1964.Associated Press

Because of sex. Over the past 55 years, that single three-letter word has had momentous legal and social consequences for American life that the man who inserted it into the 1964 Civil Rights Act on a wintry Saturday morning could never have imagined. And now that the Supreme Court has agreed to decide whether that landmark law forbids employment discrimination based on sexual orientation and gender identity, the adaptive power and enduring meaning of that plain little word is about to be tested once more.

On February 8, 1964, as the House of Representatives debated passage of the bill, Howard Smith, an ardent segregationist from Virginia, rose to propose changes to four pages of Title VII, the section of the bill barring hiring and firing “because of” race, creed, religion, or color. “After the word religion, insert sex,” Smith drawled, urging his colleagues to rectify “this grave injustice … particularly in an election year.”

The result was two hours of pandemonium on the House floor, because Smith’s amendment was seen by the frantic pro–civil-rights forces as a poison pill that might put the whole bill at risk—a bill that would end Jim Crow segregation in public accommodations, help ensure voting rights for long-disenfranchised populations, and just more or less win the Civil War, only a hundred years too late. It’s a story I recounted in my book An Idea Whose Time Has Come. Hard as it may be to fathom a half century later, the notion that women deserved protection from discrimination in employment was as controversial in some quarters as the idea that racial minorities did—and, even to some liberal Democrats, much more laughable.

The Democratic chairman of the House Judiciary Committee, an inveterate male chauvinist from Brooklyn named Emanuel Celler, was livid, warning that the language was “illogical, ill-timed, and improper,” that it would be an “entering wedge” to a constitutional Equal Rights Amendment (an idea he detested), and that it would lead, as indeed it eventually did, to the overturning of state laws aimed at protecting women with special, and lighter, working conditions and hours. (In fact, such an outcome would have pleased Howard Smith, because Virginia’s textile industry depended on cheap female labor). So worried were the bill’s supporters that Edith Green, an Oregon Democrat who nearly a decade earlier had proposed a bill to require that men and women be paid equally for equal work, now stood to read a letter from the American Association of University Women opposing the Smith amendment, and adding her own view, said, “I do not believe this is the time or the place.”

But soon a bipartisan coalition of five women took up the fight in support of Smith’s proposal. Katharine St. George, a New York Republican, was biting. “I can think of nothing more logical than this amendment at this point,” she told her male colleagues. “We outlast you. We outlive you, we nag you to death …We are entitled to this little crumb of equality. The addition of the little, terrifying word s-e-x will not hurt this legislation in any way.” In the end, the House agreed, and the measure passed, 168–133, with mostly southern and Republican support, as it happened. As the final tally was announced, one woman in the gallery shouted, “We’ve won! We’ve won!” while another cried out, “We made it! God bless America!” before male doorkeepers escorted them from the room. The Senate and House gave final passage to the whole bill that summer.

Would Hubert Humphrey, Everett Dirksen, Mike Mansfield, and the other legislative lions who shepherded the 1964 Civil Rights Act ever have imagined that the law might one day be invoked to safeguard the rights of LGBTQ people, a then-unheard-of abbreviation that they might have taken for a mashed-up mix of New York subway lines? Probably not. But neither would plenty of those legislators have imagined—or been pleased—that a law that most of them saw as a color-blind expression of faith in the American creed eventually led to color-conscious remedies such as affirmative action in education and hiring. As William McCulloch of Ohio, the bill’s staunchest GOP supporter in the House, told Smith at one point in the debate, quoting the poet James Russell Lowell, a founder of this magazine:

                   New occasions teach new duties;

                   Time makes ancient good uncouth;

                   They must upward still, and onward,

                   who would keep abreast of Truth.

When Title VII was passed, just two states in the union—Hawaii and Wisconsin—had laws prohibiting sex discrimination in employment. Today, 21 states expressly prohibit discrimination against gay, lesbian, and transgender employees in the workplace, and this week, lawyers for the American Civil Liberties Union told the Los Angeles Times that most Americans assume the federal government already does too.

The language of any law has transmutative consequences that its most ardent advocates—and its most determined foes—might never envision. After the passage of the 1964 act, lawyers at the newly created Equal Employment Opportunity Commission were flummoxed by the wave of gender-discrimination complaints that they received. Members of its staff wondered what to do with these complaints, and how many resources it should devote to them, one of them told me, when everyone understood that the real point of the law was ending racial discrimination. It turns out that the real impact of the law was to address both, as a pioneering young lawyer named Ruth Bader Ginsburg would soon prove in court again and again.

Heaven only knows what the current Supreme Court will make of the cases it agreed to hear next term. In one of them, involving a gay skydiving instructor in New York who was fired after casually mentioning his sexual orientation, a lower court found that the dismissal violated Title VII’s prohibition on discrimination “because of” sex. A Michigan court reached a similar finding in the case of a transgender woman who was dismissed from her job at a funeral home after she announced her intention to transition from the male identity she had at birth. In a third case, in Georgia, a child-welfare worker who said he was gay was fired because of his orientation, and an appeals court in Atlanta ruled against him in a brief, unsigned opinion, citing a 1979 decision that had held that “discharge for homosexuality is not prohibited by Title VII.”

But gay-rights advocates have at least some reason for hope in precedent, and in the words of one of the Supreme Court’s most conservative modern-era members, Antonin Scalia, who wrote the majority opinion in a 1998 case involving a claim of sexual harassment by a male oil-platform worker who contended that other men on the rig had harassed him: “Male-on-male sexual harassment was assuredly not the principal evil Congress was concerned with. But statutory prohibitions often go beyond the principal evil to cover reasonably comparable evils, and it is ultimately the provisions of our laws rather than the principal concerns of our legislators by which we are governed.”

The legislative climate that produced the 1964 Civil Rights Act is as distant from our own day as candlelight and clipper ships. The final bill passed the Senate 73–27, with 27 Republican votes. But the debate over its passage was every bit as bitter and divisive as any contemporary argument. At the height of his fight against it, Howard Smith complained that the bill was “as full of booby traps as a dog is of fleas.” How fitting, then, that all these years later, Smith’s own little flea-bitten booby trap might just yet again produce a once-unanticipated but salutary result.

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