Since at least a decade ago, a rare consensus has prevailed on a provocative issue for L.G.B.T.Q. people. Professional counseling aimed at changing the sexual orientations of gay teenagers, sometimes known as conversion therapy, was viewed as harmful and widely rejected.

The American Medical Association dropped support for programs offering gay patients “the possibility of sex preference reversal” in 1994. In 2009, the American Psychological Association concluded that “sexual orientation change efforts” could be harmful, inducing “depression, suicidal ideation, self-blame, guilt and loss of hope” in some people. A few years later, Exodus International, the largest Christian ministry promising to “cure” homosexuality through prayer and psychotherapy, closed after its leader apologized to gay men and lesbians and said he no longer believed people could rid themselves of those desires.

State legislatures took notice. Between 2012 and 2024, roughly half of states placed restrictions on therapy for minors that “attempts or purports to change an individual’s sexual orientation or gender identity,” in the words of Colorado’s statute. Eight of the therapy bans were signed by Republican governors, and dozens of cities and counties adopted similar limitations.

But as debates over gay rights have given way to a national focus on transgender identities, questions about what sorts of therapy should be off-limits for L.G.B.T.Q. youth are being revisited. Some groups are pushing for talk therapy that steers children and adolescents who identify as transgender to live in accordance with the sex they were assigned at birth. This push, which is playing out in legislatures and courts, and fueling discussion among mental health professionals and parents, has led to a new round of sparring over whether such therapy would inflict the sort of harm on minors that led experts to reject conversion therapy for gay and lesbian teenagers.

Kelsy Burke, a sociologist at the University of Nebraska, Lincoln, who has tracked public opinion polling on how Americans view L.G.B.T.Q. rights, said the shift in the consensus around such talk therapy reflected a growing discord over the nature of transgender identity.

“Conversion therapy had an image problem in that the messaging was about making someone straight, and that was losing appeal broadly in American culture,” Dr. Burke said. “But there’s this new moment when it comes to debates about transgender rights that is allowing conversion therapy to be back on the table.”

On Tuesday, the Supreme Court will hear arguments in a case challenging a ban in Colorado by a counselor who says she wants to help patients with their stated goals, which might include seeking “to reduce or eliminate unwanted sexual attractions,” or to “grow in the experience of harmony with one’s physical body,” according to her filings. The counselor, Kaley Chiles, argues that the ban is an unconstitutional restriction of her free speech rights; Colorado says it is regulating a form of treatment that may harm minors.

Beyond the free speech question, the issue of therapy has become part of a policy debate over the best way to care for minors who are transgender or are grappling with their gender identities.

Some psychotherapists argue that there is a difference between pressuring transgender children to renounce their gender identities and exploring through counseling why they may feel that their bodies are not aligned with their inner sense of gender. In the case before the Supreme Court, another state-licensed therapist in Colorado with conservative religious beliefs submitted a brief arguing that therapists are not, in fact, constrained by the conversion therapy bans in their states from exploring conflicts over sexual orientation and gender identity with young patients.

Mental health professionals and legal experts say the question of when exploring conflicts goes too far may not be settled by the case. Should the bans be found unconstitutional, minors who believe they were harmed by therapy could sue under consumer protection laws. And the ethical debate among counselors is likely to continue.

“When there’s an underlying premise that there is a fixed, predetermined outcome for what is correct and what is not correct, then that is an unethical approach to care,” said Dr. Scott Leibowitz, a child and adolescent psychiatrist who is on the board of the World Professional Association for Transgender Health, a leading professional organization for gender clinicians. “The problem is that sometimes people don’t know when they’re crossing that line. And that’s what’s insidious about the issue.”

Recent changes in state laws and federal policy under the Trump administration have barred many children with a diagnosis of gender dysphoria from access to medications that can ease their symptoms by pausing puberty or adjusting traits like voice depth, breast development and facial hair to be more in line with their gender identity. Pathways to social acceptance, including allowing trans children to use bathrooms, play on teams and be called by pronouns that correspond to their sense of gender, are also newly prohibited by law and policy in many places.

The major medical organizations in the United States endorse social and medical transition as effective in relieving the psychological distress many transgender youths experience, an approach known as gender-affirming care. And WPATH, the transgender health professional association, recommends that minors experiencing distress associated with gender dysphoria undergo a psychological assessment before anything else. But as the number of young people seeking medication for gender transition has grown, the field has been criticized — including by some prominent members — for moving too quickly to affirm minors who identify as transgender, citing the risk that some may regret transitioning.

Now, some parents, legislators and therapists say that an approach they call exploratory therapy could be included in the mix of treatments, offering an option for trans minors and their parents to try therapy focused on the gender that corresponds with their sex.

This spring, in response to an executive order by President Trump, federal health officials published a report that characterized psychotherapy as a preferable, “noninvasive alternative” to medical treatments for children with gender dysphoria. The authors of the report, whose names were not disclosed, concluded that there had been too little research on psychotherapeutic approaches to treating gender dysphoria, which they suggested was “due in part to the mischaracterization of such approaches as ‘conversion therapy.’”

And in several states, restrictions on counseling for L.G.B.T.Q. young people have recently been reconsidered, with gender identity as a focal point. David Walls, the executive director of the Family Foundation, which is based in Kentucky and supports “God-honoring public policy,” noted that lawmakers there overturned an executive order prohibiting the use of state funds on conversion therapy for minors in March.

“Any efforts that are seeking to prevent children from counseling that would simply just ensure that they’re able to identify in alignment with their actual biology, we view those efforts as harmful,” Mr. Walls said.

In June, officials in Columbia, S.C., rescinded a conversion therapy ban after the state said it would stop funding the city unless it did so. The following month, Virginia officials announced that they would no longer enforce a state ban as they settled a lawsuit brought by a licensed counselor.

Some therapists and religious advisers bristle at the term “conversion therapy,” which has taken on a pejorative connotation. It serves as an umbrella for a range of practices that once centered on physical interventions like electric shock and chemically induced nausea. But major health care associations said that speech-based techniques to conform to traditional gender roles, like encouraging patients to trace the causes of their sexual orientations to emotional scars in childhood, had been proven to inflict their own forms of damage.

The push to prohibit such practices for gay minors was driven by the growing belief that sexual orientation is so central to a person’s identity that no one should be asked to change it, researchers said. In 1977, a majority of U.S. adults thought being gay or lesbian was because of upbringing and environment, according to a Gallup poll, while 13 percent saw it as determined at birth. By 2012, the percentage believing sexual orientation is determined at birth had grown to 40 percent, crossing over to a majority in 2015, the year the Supreme Court established same-sex marriage as a national right.

Many trans people say their gender identities are a simple fact of their existence, which, like sexual orientation, is not chosen. They say that any therapy that starts with a premise that gender identity can be changed — or is not real — is a form of conversion therapy, with all of its potential harms.

“Therapy can be a very helpful tool for any of us to find ourselves,” said Clare Killman, a transgender woman and member of the Carbondale, Ill., City Council, who has spoken publicly about her experience undergoing conversion therapy techniques as a teenager. “But the quality of being trans is inherent within the human condition. No amount of therapy is going to make that change.”

She added: “I was trans before the therapy, I endured the therapy, and guess what? I’m still trans.”

Those seeking to overturn conversion therapy bans, like Erin Friday, president of a California parent group called Our Duty U.S.A., argue that transgender identity is not something you’re born with. Ms. Friday, who said she had long supported same-sex marriage and opposed conversion therapy for gay men and lesbians, believes that many children who identify as transgender do so because they are influenced by peers or social media.

California’s 2012 ban on “efforts to change behaviors or gender expressions” for minors, Ms. Friday said, makes it difficult for therapists to provide the kind of counseling she sought for her own child, who she said began openly identifying as transgender around age 13, in 2020.

“You call for help, and then you call around, and you try to get any doctor in California to help you with your severely depressed daughter,” she added. “And all you get are affirming doctors that are telling you that you need to now accept your son, your newly minted son.”

Some L.G.B.T.Q. activists say that whether being gay or having a transgender identity has a biological basis is beside the point. The cultural interest in changing members of both categories, they say, is connected to a similar wish to return them to the expectations of appearance and behavior associated with their sex.

Garrard Conley is a professor at Kennesaw State University in Georgia whose 2016 memoir recounts his experience as a teenager attending the therapy group Love in Action, which described itself as an “ex-gay” organization that helped individuals “overcome” same-sex attractions.

Mr. Conley recalled being told not to “lean” while standing and to watch sports. A fellow male participant, he said, was reprimanded for a high-pitched sneeze.

“So much of conversion therapy pitted what we knew to be true against ourselves,” Mr. Conley said. “And it was all based off of gender stereotypes.”