LGBTQ groups say transgender people face growing threats of violence and discrimination in the US.

On Friday, the 11th US Circuit Court of Appeals ruled in a seven-to-four decision that the policy – instituted by a school board in St Johns County, Florida – did not violate the US Constitution’s Equal Protections Clause or federal civil rights law.

“This is an aberrant ruling that contradicts the rulings of every other circuit to consider the question across the country,” said Tara Borelli, a lawyer with the LGBTQ civil rights organisation Lambda Legal, which was involved in the case. “We will be reviewing and evaluating this dangerous decision over the weekend.”

The ruling is a victory for conservatives who have sought to impose strict conceptions of gender on institutions across the country. In May, Oklahoma became the latest state to sign a so-called “bathroom bill” into law, requiring students in public schools to use restrooms, changing rooms and showers that correspond to the sex indicated on their birth certificate.

LGBTQ groups have fought back, accusing legislators of stirring up fear and resentment against transgender individuals. Lambda Legal is also challenging the Oklahoma law in federal court.

The St Johns County policy likewise forced transgender students to use toilets corresponding to the biological sex they were assigned at birth rather than their chosen identity.

The policy was challenged in 2017 by Drew Adams, a transgender man who was not allowed to use the men’s restroom when he was a student at Allen D Nease High School in Ponte Vedra Beach, Florida.

US President Joe Biden’s administration had urged the circuit court to strike the rule down, but the court voted to uphold it. Six of the seven judges in the majority were appointed by former President Donald Trump, a Republican, who rolled back protections for transgender people during his time in office.

States and local jurisdictions across the US have continued to pursue policies that critics say discriminate against transgender people, including legislation that would ban transgender youth from participating in sports teams and competitions that correspond with their gender identity.

Earlier this month, a lawsuit was also filed against the US state of Georgia, alleging the state’s health insurance policy illegally discriminates by refusing to pay for gender-affirming healthcare.

“The exclusion communicates to transgender persons and to the public that their state government deems them unworthy of equal treatment,” the lawsuit argues.

LGBTQ people in the US have raised concerns that heated rhetoric directed at them by conservative figures has contributed to a combustible environment and an “epidemic of hate”.

Right-wing groups, sometimes including members of armed militias, have protested against drag shows across the US. In Boston, a children’s hospital that offers gender-affirming medical treatment has faced numerous bomb threats. And a gunman attacked an LGBTQ nightclub in Colorado last month, killing five people and injuring at least 17 others.

In December, Biden signed a law protecting same-sex marriage rights amid concerns the country’s Supreme Court, which has a sizeable conservative majority, could roll back protections previously granted to LGBTQ people.

“This law and the love it defends strike a blow against hate in all its forms, and that’s why this law matters to every single American, no matter who you are and who you love,” said Biden at the signing ceremony.