Every House Democrat but one has co-sponsored a bill requiring schools to allow male athletes who identify as transgender girls to compete on female sports teams.

Democrats’ Equality Act would amend the Civil Rights Act of 1964 to make “sexual orientation and gender identity” protected characteristics under federal anti-discrimination law. Among other things, the bill would force public schools to expand female athletic teams to include biological males who identify as transgender girls.

Sarah Warbelow, director of the left-wing Human Rights Campaign, praised the bill’s impact on high school sports in written testimony submitted to a House subcommittee on Tuesday.

“Opponents of equality in athletics for transgender athletes have argued that girls who are transgender have unfair physiological advantages over cisgender girls and as a result, will dominate women’s competitive sports,” Warbelow wrote, calling it not “rooted in fact” that biologically male athletes will outperform their female counterparts.

House Judiciary Chairman Jerry Nadler, a Democrat from New York, made a similar argument during an April 2 hearing his committee held on the legislation. (RELATED: Biological Male Is Top-Ranked NCAA Track Star)

“Many states have sexual orientation and gender identity nondiscrimination laws, and all of them still have women’s sports. Arguments about transgender athletes participating in sports in accordance with their gender identity having competitive advantages have not been borne out,” Nadler said in his opening statement.

In Connecticut, one of the states to which Nadler was referring, two male runners have dominated girls’ high school track. A female competitor called the male runners’ advantage “demoralizing.”

Julia Beck, the head of a self-described radical feminist organization, testified against the bill.

The Democrats’ bill would lead to a male invasion of female spaces, including on the athletic field, Beck said in her April 2 testimony. “Men will dominate female sports,” she warned.

Of the 235 Democrats in the House, 234 have co-sponsored the legislation. (That’s not counting Washington, D.C., and Puerto Rico’s non-voting representatives, who also signed on as co-sponsors.)

Reps. John Katko of New York and Brian Fitzpatrick of Pennsylvania are the only House Republicans to co-sponsor the bill.

Illinois Rep. Dan Lipinski, the only pro-life Democrat left in the House, is also the only one in his party not co-sponsoring the Equality Act.

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