Last week, a bare majority of the Supreme Court — five out of nine justices — refused to issue an injunction against a Texas statute making it illegal for physicians to perform an abortion if they detect cardiac activity in an embryo or fail to test for such activity. As Justice Sonia Sotomayor explained in her dissent, “This equates to a near-categorical ban on abortions beginning six weeks after a woman’s last menstrual period, before many women realize they are pregnant, and months before fetal viability.”

The Texas statute could be enjoined by another court, or by the Supreme Court in a later appeal. Meanwhile, another abortion case will be heard by the Supreme Court in November, this time with full briefing and oral argument, which did not happen in the Texas case. The November case involves a Mississippi law that prohibits almost all abortions after 15 weeks gestational age.

A panel of the Fifth Circuit Court of Appeals struck down the Mississippi statute, noting that, since Roe v. Wade, decided more than 48 years ago, “the Supreme Court’s abortion cases have established (and affirmed, and re-affirmed) a woman’s right to choose an abortion before viability. States may regulate abortion procedures prior to viability so long as they do not impose an undue burden on the woman’s right, but they may not ban abortions.”

In appealing the Fifth Circuit’s decision, Mississippi is asking the Supreme Court to reverse nearly five decades of its abortion jurisprudence. Mississippi’s brief states that Roe and Planned Parenthood of Southeastern Pennsylvania v. Casey (the 1992 case setting forth the “undue burden” standard) are “egregiously wrong,” “hopelessly unworkable,” “have inflicted profound damage,” and should be overruled. “Nothing but a full break from these cases can stem the harms they have caused.”

Last week’s decision, in which conservative Chief Justice John Roberts joined the three liberal justices and would have enjoined the Texas law, shows that there may now be a majority of Justices ready to overrule Roe and Casey. Clarence Thomas and Samuel Alito have argued that position in dissenting opinions for years. Neil Gorsuch, Brett Kavanaugh and Amy Coney Barrett have all written articles and made speeches implying that the Court’s normal practice of stare decisis, of adhering to precedent, should not apply when it comes to Roe and Casey.

If Roe and Casey are overruled, or substantially limited, action on abortion policy will turn to state legislatures. Eleven states have already enacted so-called trigger laws that would prohibit nearly all abortions, without any further legislative action needed, should the Supreme Court overturn Roe. Lawyers at the Center for Reproductive Rights say legislatures in another 10 to 20 states could pass bills substantially restricting pre-viability abortions should the Supreme Court uphold Mississippi’s 15-week ban.

Legislatures in a few states could respond by further protecting abortion rights. Vermont will fall into this group, regardless of what the Supreme Court decides in the Mississippi case. When the Legislature returns in January, the House will take the final steps to put a proposed amendment to the Vermont Constitution on the November 2022 ballot. This amendment has already been passed twice by the Senate, and once by the House, in all instances by a substantial tripartisan majority.

The proposed “personal reproductive liberty” amendment reads: “That an individual’s right to personal reproductive autonomy is central to the liberty and dignity to determine one’s own life course and shall not be denied or infringed unless justified by a compelling State interest achieved by the least restrictive means.” Ratification of the amendment by the voters in November would make reproductive liberty one of the rights protected in the Vermont Constitution, and would allow the Vermont Legislature to enact policies consistent with that right, regardless of the course taken by the Supreme Court and other federal courts.

Eric L. Davis is professor emeritus of political science at Middlebury College.