The Kansas Supreme Court has ruled that the state’s constitution fundamentally protects abortion rights, blocking a state law that aimed to restrict a common procedure and declaring that Kansans have broad rights to control what happens to their own bodies regardless of federal court decisions.

Judges ruled 6 to 1 on Friday that the Kansas constitution protects the “right of personal autonomy,” meaning state law cannot abridge the right “to control one’s own body, to assert bodily integrity, and to exercise self-determination. This right allows a woman to make her own decisions regarding her body, health, family formation and family life — decisions that can include whether to continue a pregnancy.”

[Read the Kansas Supreme Court decision]

Abortion rights advocates immediately seized on the ruling as a landmark decision that could have widespread implications, providing a pathway to override restrictive state laws elsewhere. They also believe it could help battle potential federal court efforts to limit abortion rights protected by the 1973 Roe v. Wade decision. Those who oppose abortion said the ruling was extreme, and Kansas groups vowed to seek an amendment to the state constitution — as other states have — to curtail certain abortion rights.

The state high court’s ruling blocked a 2015 Kansas law that banned a second-trimester abortion procedure. The ruling comes as more than 11 Republican-led states across the Midwest and the South have supported laws banning abortion procedures after six weeks — before most women know they are pregnant. Many of those bans are facing challenges in court.

“Today’s ruling should provide an example to all other courts in the nation grappling with these critical questions,” said Elizabeth Wydra, president of the Constitutional Accountability Center, a liberal think tank and law firm that supports abortion rights and has made constitutional arguments in favor of same-sex marriage and affirmative action.

“As the framers of the Kansas Constitution explained, the immortal words of the Declaration of Independence are a call to secure ‘wide liberty’ and to ensure ‘to every individual perfect freedom to enjoy in safety and tranquility the rights and blessings of that existence,’ ” she said.

Mary Kay Culp, spokeswoman for Kansans for Life, an antiabortion group, said the court’s ruling was “horrendous and more extreme than even we expected.”

Culp said her group will push to organize a comprehensive movement to amend the state constitution to make it “crystal clear there is no state constitutional right to abortion here that somehow trumps 45 years of pro-life legislation.”

The state’s treasurer, Jake LaTurner, a Republican, issued a statement calling the decision “an abomination” that marked “one of the darkest days in our state’s history.”

Four of the justices on the Kansas panel were appointed by former governor Kathleen Sebelius, a Democrat who went on to be President Barack Obama’s heath and human services secretary. The remaining three were appointed by Republicans; the lone dissenter, Justice Caleb Stegall, was appointed in 2014 by then-Gov. Sam Brownback (R).

Stegall wrote that the court’s ruling is “the most significant and far-reaching decision this court has ever made” and argues that the majority fundamentally altered the state’s structure of government to hew toward a “favored policy.” He wrote that it paints “the interest in unborn life championed by millions of Kansans as rooted in an ugly prejudice.”

Antiabortion activists fear the court’s ruling could negatively affect previous legislative restrictions in Kansas, including measures that require women to undergo an ultrasound and receive counseling before an abortion, and that require parental consent before a minor can have an abortion.

The Kansas Supreme Court’s decision potentially provides a bulwark against any decisions the U.S. Supreme Court might make in abortion cases at a time when abortion rights activists fear it could reverse course on Roe with a clear conservative majority in place, experts said.

At least nine other states have constitutions that specifically protect a woman’s right to an abortion, according to state high court rulings: Alaska, California, Florida, Iowa, Massachusetts, Minnesota, Montana, New Jersey and New Mexico. Other states, including Connecticut, Delaware, Hawaii, Maine, Maryland, Nevada, New York, Oregon and Washington have statutory protection for abortion rights, according to the Center for Reproductive Rights.

Experts said other states could look to use their constitutions to assert wide-ranging protections from antiabortion laws, but states also could use the Kansas decision to legitimize strict enforcement of abortion laws if similar rights are not codified in state constitutions. It also could spur efforts to seek constitutional amendments — as Culp plans to do — that limit abortion rights. Tennessee, for example, amended its constitution in 2014 to eliminate that right, and the U.S. Supreme Court declined to hear a challenge to the measure last year.

“Although this is a sad day for Kansas, we are hopeful that this extreme opinion will spark a movement to amend the Kansas constitution — as West Virginia, Tennessee, and Alabama have done — to return the issue of abortion to the people and their elected representatives,” said Catherine Glenn Foster, president of Americans United for Life.

Those who oppose abortion are working on several ways to limit abortion in the states and through Congress, and they are hopeful that a case will reach the U.S. Supreme Court so that justices can consider broadly restricting abortion rights.

Congress still has the power to pass laws restricting abortion — such as late-term abortions, for example — and a federal ban would supersede any state law, said Michael I. Meyerson, a professor at the University of Baltimore School of Law.

“The Kansas decision protects the women of Kansas from the Supreme Court, but not from Congress,” Meyerson said.

Genevieve Scott, a senior staff attorney at the Center for Reproductive Rights, which challenged the measure in court on behalf of two doctors who perform abortions in Kansas, said the ruling was exactly what they had hoped would emerge from the case. Scott said the ruling will make it difficult for state legislators or the federal government to restrict access to abortion in Kansas.

“This will make Kansas a haven state in the Midwest if federal laws protecting abortion are overturned or significantly limited or undercut in other states,” Scott said.

Kansas has long been at the center of the abortion debate: During the mid-1990s, the state was seen as one of the least-restrictive in the country, and in 2009 George Tiller, one of the country’s few third-trimester abortion providers, was assassinated in Wichita by an antiabortion extremist.

The state again appears to be at a crossroads on a political issue that has long divided much of the country.

Newly elected Kansas Gov. Laura Kelly — a Democrat and an abortion rights supporter — has been facing off with a Republican legislature that has instituted some of the most stringent abortion restrictions in the nation.

Kelly took office in January after former governor Sam Brownback — now President Trump’s ambassador for international religious freedom — had made antiabortion legislation the hallmark of his two terms in office, including the 2015 measure the court blocked Friday.

“While federal law has long guaranteed every woman the right to make their own medical decisions in consultation with their health care providers, I’m pleased that the Kansas Supreme Court’s decision now conclusively respects and recognizes that right under Kansas law as well,” Kelly said Friday.

On Monday, Kelly vetoed a measure — a so-called abortion-reversal bill — that would have required clinics and doctors to tell patients that it is possible to reverse a medically induced abortion even after taking the first of two pills used to end a pregnancy.

Kelly said the measure was confusing and could harm the doctor-patient relationship. However, Republicans might have enough votes to override her veto when they return from a break on May 1, analysts said.

The court’s decision on Friday stems from a 2015 law that sought to ban dilation and evacuation, a method used in 95 percent of second-trimester abortions. The procedure involves using surgical tools to remove the fetus.

The lawsuit challenging the Kansas measure was filed by Herbert Hodes and Traci Nauser, father and daughter, both of whom are doctors who operated a women’s health center in the Kansas City suburb of Overland Park. Hodes has since retired.

The ban was the first state law of its kind but never took effect because of legal challenges.