Transgender athletes are getting an ally in the White House next week as they seek to participate as their identified gender in high school and college sports — although state legislatures, Congress and the courts are all expected to have their say this year, too.

Attorneys on both sides say they expect President-elect Joe Biden’s Department of Education will switch sides in two key legal battles — one in Connecticut, the other in Idaho — that could go a long way in determining whether transgender athletes are treated by the sex on their birth certificates or by how they identify.

Debate is also expected in statehouses. Last year, bills to restrict transgender athletes' participation to their gender assigned at birth were brought up in 17 states, although only one, Idaho's, became law.

It may ultimately fall to Congress to clarify once and for all whether Title IX, the civil rights law that guarantees equal opportunities for women and girls in education, protects or bars the participation of transgender females in women's sports, said Elizabeth Sharrow, an associate professor of public policy at the University of Massachusetts.

“I think if they do that, lawmakers at the state level can propose laws, but it doesn’t mean those proposals are going to be taken seriously in the legislative bodies they serve in or that if the state passes those laws anyway that they would necessarily be considered legitimate,” she said. “The courts will sort that out.”

During his campaign, Biden committed to restoring transgender students’ access to sports, bathrooms and locker rooms in accordance with their gender identity.

“States that like Idaho attempt to bar trans girls from girls sports, regardless of age of transition, medical intervention or anything else, with a new federal administration, will now be risking lawsuits by the federal government, Justice Department intervention and the loss of federal funding,” said Chase Strangio, the American Civil Liberties Union’s deputy director for transgender justice.

In Idaho, a law signed in March became the nation's first to prohibit transgender students who identify as female from playing on female teams sponsored by public schools, colleges and universities. The law was supported by President Donald Trump’s administration but blocked from implementation by a federal judge while a legal challenge by ACLU proceeds.

“Allowing males to enter our sports isn’t fair," Madison Kenyon, a cross-country runner at Idaho State, said in a statement Friday. "It changes everything because it eliminates the connection between an athlete’s effort and her success. Idaho’s law helps make sure that, when women like me work hard, that hard work pays off, and we have a shot at winning.”

In Connecticut, the Trump administration intervened in support of a lawsuit filed by several non-transgender girls in Connecticut who were seeking to block a state policy that allows transgender athletes to compete in line with their identity. The plaintiffs argued transgender female runners had an unfair physical advantage.

But the two transgender runners at the center of that case said in court filings that being able to run against girls was central to their well-being.

“Running has been so important for my identity, my growth as a person, and my ability to survive in a world that discriminates against me,” Andraya Yearwood wrote to the court. “I am thankful that I live in Connecticut where I can be treated as a girl in all aspects of life and not face discrimination at school.”

Neither of the two closely watched cases is expected to be decided for months. A federal judge has scheduled a hearing for Feb. 26 on a request to dismiss the Connecticut lawsuit.

The ACLU and the Christian nonprofit Alliance Defending Freedom, which is fighting in Connecticut and Idaho to bar the participation of trans athletes, expect Biden’s administration to declare that Title IX also protects transgender girls from discrimination.

Opponents say Title IX protects cisgender girls and allowing trans girls to participate against them is a violation of the statute.

“I think that is extremely concerning for the future of women’s sports and would reverse nearly 50 years of gains for women under Title IX,” said Christiana Holcomb, an attorney for the Alliance Defending Freedom.

In states that have adopted policies on transgender participation high school sports, approaches have varied.

Currently, 14 states and the District of Columbia have policies similar to Connecticut’s, according to Transathlete.com. Fourteen others allow transgender participation with certain conditions, such as hormone treatments or other proof the athlete is transitioning, according to the organization.

Opponents of bans are encouraged by Biden's victory and a 2020 Supreme Court decision that found that transgender people are protected from discrimination in employment.

“It’s possible that the Connecticut case could evaporate under a new administration that doesn’t want to press it,” said Erin Buzuvis, a professor at the Western New England School of Law who specializes in gender and discrimination in education and athletics.

“The Idaho situation is different because it is a state law that is being challenged under the equal protection doctrine," Buzuvis said. "That could set some sort of national standard about what kind of policies states are allowed to have or prohibited to have. But that doesn’t necessarily mean that the case would say, ‘Here is the one policy that all states must have.’”