Democratic presidential candidate Sen. Elizabeth Warren has branded a proposed ban on transgender student athletes in Arizona “cruel.”

Warren responded on Twitter to Republican state Rep. Nancy Barto’s “Save Women’s Sports Act,” which last week was approved by an Arizona House committee and will be voted on over the coming weeks.

The bill, which applies to K-12 schools, community colleges, and state universities, would allow only those assigned female at birth to compete on female athletic teams.

If a person’s gender identity were called into question, that athlete would be required to obtain a doctor’s note proving they are female before being allowed to compete.

The bill would also allow cisgender female students who believe they’ve missed out on athletic opportunities because of transgender inclusion on a school team to file lawsuits seeking redress.

“Trans athletes are not a threat,” Warren tweeted. “We need to protect trans kids — and all LGBTQ+ kids — and ensure they feel safe and welcomed at school. I urge the Arizona legislature to reject this cruel bill.”

Trans athletes are not a threat. We need to protect trans kids—and all LGBTQ+ kids—and ensure they feel safe and welcomed at school. I urge the Arizona legislature to reject this cruel bill. https://t.co/9ALVjeIBiv — Elizabeth Warren (@ewarren) February 20, 2020

Barto previously defended her bill by saying, “Science is what it is. The difference between males and females is obvious.”

Opponents of the bill, including Arizona Democrats, argue that the measure will effectively ban transgender females from participating in sports altogether, as they may not want to compete against cisgender males, and could be putting themselves at risk of abuse or harassment by teammates if they were to compete on male sports teams.

Arizona’s move follows other Republican-led initiatives to restrict transgender athletes from competing in sports in accordance with their gender identity.

Republicans in Georgia, Tennessee, and Washington state are pushing such bans for the 2020 legislative session.

Shannon Minter, legal director for the National Center for Lesbian Rights, told the Arizona Republic that there is “a reason these bills are popping up simultaneously.”

“There have been no problems with this issue in Arizona. This isn’t responding to an issue that students are having in Arizona. This is a national campaign to use this issue — sadly — to just polarize and divide people,” Minter said.

For Warren, it’s the latest example of support for the transgender community. Last week, she used nonbinary-inclusive terms in a tweet discussing a potential vice presidential pick, and the Massachusetts senator includes her preferred pronouns in her Twitter bio.

I want to tell you exactly the kind of vice president I want: Someone who will be in this fight alongside me for your families. Someone who feels this fight passionately—and who brings his, her, or their own energy to get it done. #CNNTownHall — Elizabeth Warren (@ewarren) February 21, 2020

Warren has also repeatedly highlighted the epidemic of violence against transgender women — particularly trans women of color — in the United States, including reading out the names of women who have been killed and raising the issue of anti-trans violence during Democratic debates.

During a debate in December, Warren and Sen. Bernie Sanders were asked what they would do to “stop violence against transgender people.”

While Sanders pivoted to discussing Medicare for All, Warren pledged to “go to the Rose Garden once every year to read the names of transgender women, of people of color, who have been killed in the past year.”

“I will make sure that we read their names so that as a nation we are forced to address the particular vulnerability on homelessness,” Warren said. “I will change the rules now that put people in prison based on their birth sex identification rather than their current identification.”

She added: “I will do everything I can to make sure that we are an America that leaves no one behind.”

Like other candidates seeking the Democratic nomination, Warren has also committed to reverse Donald Trump’s ban on transgender people serving openly in the U.S. military, branding the ban “shameful” in a tweet last year.

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