A letter posted Wednesday to WhiteHouse.gov thanked visitors for signing a petition in support of banning “conversion therapy” for LGBTQ young people. So-called conversion therapy, also known as “reparative therapy,” seeks to change a person’s sexual orientation or gender identity.

It has been found to be psychologically harmful and has been rejected by the American Psychological Association and other major medical organizations.

California, New Jersey, and Washington, D.C., have all banned the practice for minors. While the Obama administration is not planning to introduce a federal ban on the practice, it is throwing its weight behind efforts to implement “Leelah’s Law” in states across the country.

The proposed law honors Leelah Alcorn, a 17-year-old trans women who committed suicide last year. Alcorn, in an online suicide note, explained that religious therapists had tried to make her identify as a boy.

Valerie Jarrett, a senior advisor to President Obama and author of the White House’s letter of support, spoke of Alcorn’s death in an interview with the New York Times: “It’s tragic, but I will tell you, unfortunately, she has lots of company. It’s not the story of one young person, it’s the story of countless young people who have been subjected to this.”

Reparative therapy became popular in the 1970s and 1980s when mainstream medical associations stopped viewing homosexuality as a mental illness and declared that the goal of mental health care for gay and lesbian people should not be to “cure” them but to help them cope with a homophobic society.

The goal of conversion therapy—which is often practiced by religious leaders rather than mental health experts—is to try and change a person’s sexual orientation, or in the case of a transgender person, to try and alter their gender identity.

Reparative therapy practices include everything from self-guided Bible study to aversion shock therapy, in which electrodes are placed on a patient’s body while they watch gay pornography and shocks are administered every time they become aroused.

A 2009 report by the American Psychological Association looked at 83 peer-reviewed studies conducted between 1960 and 2007 and found no legitimate evidence that this type of therapy was effective. The research showed that most studies on the subject had serious methodological problems, none were based on credible scientific theory, and many were based on theories that could never be scientifically evaluated.

The report concluded that efforts to change same-sex attraction are not only ineffective, but also cause harm, including loss of sexual feeling, depression, thoughts of suicide, and anxiety. The American Medical Association, the American Psychiatric Association, and the American Academy of Pediatrics oppose this practice.

Many people and organizations that originally supported reparative therapy have apologized for their role in promoting this practice and the “ex-gay” lifestyle. In 2013, for example, Exodus International—which was once the largest affiliation of so-called ex-gay ministries—closed its door.

“I am sorry we promoted sexual orientation change efforts and reparative theories about sexual orientation that stigmatized parents,” said Alan Chambers, the organization’s president, as Rewire reported. “I am sorry that there were times I didn’t stand up to people publicly ‘on my side’ who called you names like sodomite—or worse.”

Reparative therapy still has some supporters today.

The National Association for Research and Therapy of Homosexuality (NARTH), which was founded on the “assumption that obligatory homosexuality is a treatable disorder,” continues to operate and refer patients to therapists like David Pickup, who also spoke to the New York Times on Wednesday.

“We believe that change is still possible. People go to therapy because they can change, because it really does work. We help people grow into their authentic selves,” Pickup said.

Pickup is actively opposing efforts such as Leelah’s Law and wants the White House to do the same. He told the Times that he wants the president to “wake up and understand the rights of people who he doesn’t know anything about and need his help and need his compassion.”

Compassion is just what Obama believes he is giving by supporting bans on conversion therapy.

“Tonight, somewhere in America, a young person, let’s say a young man, will struggle to fall to sleep, wrestling alone with a secret he’s held as long as he can remember,” Obama wrote in his letter. “Soon, perhaps, he will decide it’s time to let that secret out. What happens next depends on him, his family, as well as his friends and his teachers and his community. But it also depends on us—on the kind of society we engender, the kind of future we build.”

The WhiteHouse.gov petition to support Leelah’s Law now has more than 120,000 signatures.