Before the ratification of the 19th Amendment 100 years ago, which granted some women won the right to vote, the Constitution was written as if women “didn’t exist.” That’s how Catharine MacKinnon, a leading feminist legal scholar, described the highest law of the land at a Duke Law School event on Monday in Washington, D.C., commemorating women’s suffrage.

A century later, the Constitution is still written in a way that doesn’t expressly grant equality between the sexes. That could soon change, though: In January, Virginia became the necessary 38th state to ratify the Equal Rights Amendment, which was introduced in 1972 and prohibits discrimination on the basis of sex.

That same decade, MacKinnon was creating the legal framework to talk about workplace sexual harassment, as well as writing about other issues related to women and the law. MacKinnon said she’s in support of any gender equality amendment, but has a different vision for how best to enshrine rights for all U.S. women.

In a piece published in the Yale Law Journal in December, MacKinnon and Kimberlé Crenshaw, a legal scholar specializing in civil rights, introduced the Equality Amendment. Although it might share the same goal as the ERA, there are some important distinctions, which MacKinnon highlighted at the Duke Law event.

Here’s the essential langauge of the ERA: “Equality of rights under the law shall not be denied or abridged by the United States or any State on account of sex.”

And here’s MacKinnon and Crenshaw’s take: “Women in all their diversity shall have equal rights in the United States and every place subject to its jurisdiction.”

Two differences stick out between these two declarations. For one, “women” appears in the Equality Amendment, but not the ERA. MacKinnon said that sex-based discrimination can actually be difficult to identify — that “on account of sex” is more abstract than granting equal rights to women.

The other big piece of MacKinnon and Crenshaw’s amendment lies in addressing race, and “in all their diversity” was meant to address intersectionality, MacKinnon said. According to her, race and sex are inextricably linked: They’re both ways in which white men have wielded power in the United States, so they both ought to be addressed in a law enshrining equality.

In the same vein, MacKinnon and Crenshaw’s equality amendment goes a step further, naming various social categories that are not included in the ERA.

“This amendment includes anything, anybody, all of it,” MacKinnon said, pointing to Section 2 of the Equality Amendment.

It reads like this: “Equality of rights shall not be denied or abridged by the United States or by any State on account of sex (including pregnancy, gender, sexual orientation, or gender identity), and/or race (including ethnicity, national origin, or color), and/or like grounds of subordination (such as disability or faith).”

Naming these categories keeps the law grounded in reality and “strengthens social recognition of these problems,” MacKinnon said. After all, no law will produce social equality all by itself, she said. But “spelling out” these social categories gives the law “more of a fighting chance” to actually change existing laws and structures.

Despite the ERA’s historic ratification, many hurdles exist before it could actually take effect. It’s likely to come up against various legal challenges, including whether the time for ratification has expired. As The Washington Post reports, there’s been pushback to the enactment of the ERA from critics who argue it would erase limitations on abortion and would strip barriers between the sexes in sports, bathrooms and prisons.

But many leading feminist legal scholars see some sort of equality amendment as necessary; as a former Stanford Law School dean told The Post, the United States is the only industrialized democracy without equality for women in its constitution. What’s more, the push to renew the ERA comes as women’s rights are at the fore in various realms of American life: politics, entertainment, the media.

MacKinnon’s advice to younger women looking to create lasting change to the law?

“Don’t shut up,” MacKinnon said. “You never know the kind of difference it could make.”

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