Arkansas state legislators voted Tuesday to pass the nation’s first law banning gender-affirming medical treatments for transgender minors, overriding a veto from their governor and intense opposition from major medical organizations across the country.

Arkansas legislators voted 25 to 8 in the Senate and 71 to 24 in the House to override the veto from Gov. Asa Hutchinson (R) and approve legislation that would prohibit doctors from providing transgender minors with medical care such as puberty blockers, hormone therapies and transition-related surgeries, and from referring them for such treatments.

The legislation is the first to pass in a wave of similar bills in 18 states so far this year, part of a growing effort by conservative lawmakers to restrict the rights of transgender young people in doctor’s offices, high school sports teams and other areas of American society.

A day earlier, Hutchinson had stunned advocates by issuing a veto of the ban, calling it a “vast government overreach” and urging conservative legislators to take a more restrained approach. He said that if signed into law, the bill would interfere with physicians and parents “as they deal with some of the most complex and sensitive matters involving young people.” Hutchinson also cited opposition from leading national medical associations that said denying access to such care could jeopardize the mental health of an already vulnerable community.

“The bill is overbroad, extreme and does not grandfather those young people who are currently under hormone treatment,” Hutchinson said. “The young people who are currently under a doctor’s care will be without treatment when this law goes into effect. That means they will be looking to the black market or go out of state if they can afford it to find the treatment that they want and need. This is not the right path to put them on.”

Hutchinson said he came to his decision after hearing from doctors and transgender people in his state, saying the conversations educated and informed him. “It strengthens your compassion,” he said. “It gives you more understanding.”

The rebuke from the Republican governor came just days after Hutchinson had signed into law a ban on transgender girls competing in school sports consistent with their gender identity, as well as a bill allowing doctors to refuse treatment to a patient based on religious or moral objections. The governor’s veto of the health-care bill was seen by some advocates as a critical turning point amid a national conservative movement to strip rights from transgender young people.

But state legislators, who needed only a simple majority to override the governor’s veto, voted to pass the bill anyway, setting the stage for a potential legal battle. Lawyers with the American Civil Liberties Union vowed to challenge the ban in court.

Holly Dickson, executive director of the ACLU of Arkansas, said in a statement that state legislators “disregarded widespread, overwhelming, and bipartisan opposition to this bill and continued their discriminatory crusade against trans youth.”

“As Governor Hutchinson noted in his veto message, denying care to trans youth can lead to harmful and life-threatening consequences,” Dickson said. “This is a sad day for Arkansas, but this fight is not over — and we’re in it for the long haul. Attempting to block trans youth from the care they need simply because of who they are is not only wrong, it’s also illegal, and we will be filing a lawsuit to challenge this law in court.”

The ban could take effect as soon as three months after the legislature adjourns, Dickson said.

The Family Council, a conservative group that supported the bill, praised the legislature for passing the ban.

“This is historic legislation,” the group said. “Arkansans ought to be proud of their leaders for doing the right thing.”

During last week’s Senate vote, one of the bill’s Republican sponsors, state Sen. Alan Clark, described gender-affirming treatments as “at best experimental and at worst a serious threat to a child’s welfare.” He argued the bill would “protect children from making mistakes that they will have a very difficult time coming back from.”

But the American Academy of Pediatrics and the Endocrine Society have supported access to puberty blockers and hormone treatments for children diagnosed with gender dysphoria. Last week, Lee Beers, president of the American Academy of Pediatrics, spoke in opposition to the Arkansas bill, saying “it puts politicians rather than pediatricians in charge of a child’s medical care.”

As Hutchinson mentioned in a news conference Monday, gender-affirming surgeries are not performed in Arkansas on anyone under the age of 18. Current medical guidelines also do not recommend any medical interventions before a child reaches puberty. But once transgender children reach the early stages of puberty, medical guidelines say they can consider puberty blockers, which are reversible treatments that pause puberty and give children time to decide what to do next. Later in their teenage years, transgender adolescents can consider hormone replacement therapies, such as estrogen for trans girls and testosterone for trans boys, which create more permanent changes to their bodies.

Several studies on puberty blockers have found that transgender young people who were treated with the medications showed lower rates of depression and anxiety and demonstrated better global functioning. A study from Harvard Medical School and the Fenway Institute published in the journal Pediatrics last year showed that young people who wanted a puberty suppressant and were able to access it had lower odds of considering suicide.

“We knew this override could happen, but it is nonetheless devastating because we also know it could have deadly consequences,” said Sam Brinton, vice president of advocacy and government affairs for the Trevor Project, a suicide prevention organization for LGBTQ young people, in a statement following Tuesday’s vote on Arkansas House Bill 1570. Over the past year, the Trevor Project has supported more than 850 crisis contacts from LGBTQ youths in Arkansas, the organization said.

“It is not extreme or sensational to say that this group of young people, who already experience disproportionate rates of violence and suicide attempts, would be put at significantly increased risk of self-harm because of legislation like HB 1570 pushing them farther to the margins of society,” Brinton added.

Chase Strangio, deputy director for transgender justice at the ACLU, said in a statement that the bill will “drive families, doctors and businesses out of the state and send a terrible and heartbreaking message to the transgender young people who are watching in fear.”

One family that has lived in Arkansas for the past 16 years already launched a crowdfunding campaign this week, asking for help as they relocate to New Mexico to support their transgender son, who relies on testosterone therapy.

“He has gone from being on the verge of suicide to excitement for his future,” as a result of the testosterone treatment, the Spurrier family wrote on a GoFundMe page. “The Arkansas General Assembly has taken action to return him, and his transgender male and female peers, to that brink of self destruction.”

Some advocates and observers predicted the Arkansas bill could impact the state’s economy, comparing it to the 2016 law in North Carolina that restricted bathroom use for transgender people. The legislation, which was part of a wave of similar Republican bills at the time, prompted businesses and sports leagues to boycott the state, costing the North Carolina economy hundreds of millions of dollars.

But the North Carolina law also had another effect: It sparked a national conversation about transgender rights. In a similar way, the Arkansas bill “puts it on the agenda,” said Jami Taylor, political science professor at the University of Toledo and the author of several books on transgender rights. “It has to be talked about now.”

In the long term, Taylor predicts, this exposure could lead to shifts in attitudes that favor treatment for transgender children.

And despite the legislature’s override, Strangio tweeted, “it was and still is incredible and important” that the governor vetoed the bill. “We need to send messages to other states & signal how damaging these bills are.”

But in Arkansas, Strangio added in a statement, the “ACLU is preparing litigation as we speak.”

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