In this March 31, 2017, file photo, trans pride flags flutter in the wind at a gathering to celebrate International Transgender Day of Visibility, at the Edward R. Roybal Federal Building in Los Angeles.
Washington CNN  — 

Transgender high school students in Georgia were banned Wednesday from competing on sports teams consistent with their gender identities after the state’s high school association used a controversial new law to implement the restriction.

Republican Gov. Brian Kemp signed a bill into law last week giving the Georgia High School Association the authority to enact such a ban, a departure from similar bans in other states that came directly from their legislatures. The association, which oversees most public schools and some private schools in the state, voted unanimously to do just that on Wednesday, amending its bylaws to say that a student’s sex is determined by what is listed on their birth certificate.

“Following my signature on HB 1084, the Georgia High School Association today voted to protect fairness in school sports by unanimously approving youth to compete according to the sex determined on his/her birth certificate. I’m proud to have championed this effort in Georgia!” Kemp tweeted.

Georgia High School Association Executive Director Robin Hines told CNN on Wednesday that he was not aware of any students in the state who would immediately be affected by the decision, but that “we don’t keep information on that.” He added that the ban takes effect immediately.

The debate over the inclusion of transgender athletes, particularly women and girls, has become a political flashpoint, especially among conservatives. In pushing such measures, conservatives have argued that transgender women and girls have physical advantages ​over cisgender women and girls in sports, though a 2017 report found “no direct or consistent research” on any such advantage.

So far this year, a number of other GOP-led states have enacted such bans, including Arizona, Iowa, Oklahoma and South Dakota. Last year, Alabama, Arkansas, Florida, Mississippi, Montana, Tennessee, Texas and West Virginia enacted similar sports bans, infuriating LGBTQ advocates, who argue that conservatives are creating an issue where there isn’t one.

Opponents criticized Kemp and the Georgia High School Association on Wednesday over the new ban, with the Human Rights Campaign, one of the nation’s largest LGBTQ rights groups, saying it “deepens Georgia’s troubling track record on these issues and needlessly harms an already vulnerable population.”

“The legislative session was on the verge of adjourning last month when Gov. Kemp put his thumb on the scales to bring this topic back up. Now the Georgia High School Association has followed his example in issuing this ban, and the transgender students of Georgia will be the ones to suffer. This is a travesty and should be reversed,” Dewayne Johnson, Human Rights Campaign’s Georgia state director, said in a statement.