Rich Pedroncelli / AP file

California state Sen. Ted Lieu, D-Torrance, sponsored the bill to ban a controversial form of psychotherapy aimed at making gay youth straight.

Updated at 12:34 p.m. ET: California has become the first state in the nation to ban therapy that tries to turn gay teens straight.

Gov. Jerry Brown announced Sunday that he has signed Senate Bill 1172, which prohibits children under age 18 from undergoing “sexual orientation change efforts.”  The law, which goes into effect Jan. 1, prohibits state-licensed therapists from engaging in these practices with minors. 

"Governor Brown today reaffirmed what medical and mental health organizations have made clear: Efforts to change minors' sexual orientation are not therapy, they are the relics of prejudice and abuse that have inflicted untold harm on young lesbian, gay, bisexual and transgender Californians," Clarissa Filgioun, board president of Equality California, said in a press release.

Kate Kendell, executive director of the National Center for Lesbian Rights, added: “Governor Brown has sent a powerful message of affirmation and support to LGBT youth and their families. This law will ensure that state-licensed therapists can no longer abuse their power to harm LGBT youth and propagate the dangerous and deadly lie that sexual orientation is an illness or disorder that can be ‘cured.’”

The bill was sponsored by Sen. Ted Lieu, D-Torrance, who said bogus and unethical practices by mental-health providers to try to change a young person’s sexual orientation have resulted in irreparable psychological and emotional harm to patients.

"I am deeply honored Governor Brown signed SB 1172. The bill is necessary because children were being psychologically abused by reparative therapists who would try to change the child’s sexual orientation. An entire house of medicine has rejected gay conversion therapy. Not only does it not work but it is harmful. Patients who go through this have gone through guilt and shame, and some have committed suicide," Lieu told NBS News in a telephone interview on Sunday.

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Lieu called "gay cure" therapy "quackery" and said parents were never informed of its potentially dangerous aftereffects.

Supporters of the bill included several lesbian and gay-rights groups and mental health associations.

Among those who testified in support of the bill was Ryan Kendall, who said he underwent sexual orientation change therapy. He described his experience earlier this summer to the Assembly Business, Professions and Consumer Protection Committee:

“As a young teen, the anti-gay practice of so-called conversion therapy destroyed my life and tore apart my family. In order to stop the therapy that misled my parents into believing that I could somehow be made straight, I was forced to run away from home, surrender myself to the local department of human services, and legally separate myself from my family. At the age of 16, I had lost everything. My family and my faith had rejected me, and the damaging messages of conversion therapy, coupled with this rejection, drove me to the brink of suicide.”

The National Association for Research & Therapy of Homosexuality (NARTH), a group of therapists who believe sexual orientation can be changed, opposed the bill. It said Lieu’s claims of widespread harms to minors are not backed up by scientific research.

In a statement, NARTH said plans to seek a temporary injunction against the law.

Meanwhile, other states have inquired about the legislation. In New Jersey, Assemblyman Tim Eustace, an openly gay Democrat, said he plans to introduce legislation to outlaw conversion therapy for minors in his state.

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California moves closer to banning 'gay cure' therapy for teens

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A California lawmaker says he’s optimistic about the prospects of a bill that would make it illegal for therapists in the state to try to “convert” gay youths.

Sen. Ted Lieu, a Democrat from Torrance, says so-called “reparative” or “ex-gay” therapy wrongfully treats homosexuality as a disease and can be dangerous to minors. If his bill becomes law, California would become the first state to ban therapy aimed at turning gay and lesbian teens straight.

“Some therapists are taking advantage of vulnerable people by pushing dangerous sexual orientation-change efforts,” Lieu said before the Senate Judiciary Committee voted to approve the bill on Tuesday. “These non-scientific efforts have led in some cases to patients later committing suicide, as well as severe mental and physical anguish.”

SB 1172 now goes to the full Senate. No date for a vote has been set, but it will likely be in the next month, according to Lieu. If it passes there, it would face action in the Assembly.

“For decades, gay, lesbian, bisexual and transgender people — particularly youth — have suffered psychological abuse by those who are entrusted to care for their emotional and psychological well-being,” Clarissa Filgioun, board president of Equality California, an advocacy organization that sponsored the bill, said in a statement. “It's long past time to do everything in our power to put an end to the use of therapy tactics that have no sound scientific basis and that cause lifelong damage.”

The bill would ban children under 18 from undergoing so-called “sexual orientation change efforts,” often referred to by the acronym SOCE. It would also require adults seeking such treatment to sign informed-consent forms indicating that they understand potential dangers of reparative therapy that the bill lays out, including depression and suicide, and that it has no medical basis.

“I feel confident that the bill will pass,” Lieu told msnbc.com on Wednesday. “The facts are on our side.”

His comments came on the same day that Barack Obama became the first U.S. president to publicly back same-sex marriage. Obama said that, after reflection, he had concluded “it is important for me to go ahead and affirm that I think same-sex couples should be able to get married."

Obama: 'I think same-sex couples should be able to get married'

SOCE techniques vary and may include visualization, behavioral and social skills training components. In some extreme cases, therapists have used electric shock or nausea-inducing drugs to try to modify the behavior of gay people, according to media reports.

Lieu says decades of research by mental health experts have shown that efforts to “repair” a person’s sexual orientation can be harmful.

Several professional groups, including the American Counseling Association, the American Psychiatric Association and the American Psychological Association, have taken the position that homosexuality is not a mental disorder, and therefore there is no need for a “cure.”

Rich Pedroncelli / AP

State Sen. Ted Lieu, D-Torrance, on Tuesday urged lawmakers to approve his bill to ban a form of psychotherapy aimed at making gay people straight.

Opponents of Lieu’s bill say it’s wrong to single out one form of therapy.

David Pickup, a licensed marriage and family therapist in California who says he was once gay and became heterosexual after undergoing reparative therapy starting in his 30s, says a ban would prevent some people from recovering from trauma of sexual abuse.

Pickup, who trained under the supervision of psychologist Joseph Nicolosi -- considered by many to be the father of modern reparative therapy -- traveled to Sacramento on Tuesday to testify against the bill.

He said its backers are "egregiously misquoting the science” by contending that all SOCE is harmful. He also said the bill “takes away parents’ rights to have any input on their sons’ and daughters’ ambiguousness about sexuality.”

“I was one of those abused boys, so people like me can’t receive this kind of help, which in my opinion is just horrific,” Pickup told msnbc.com. “I’ve dealt with these issues and come out extremely happy. Reparative therapy saved my life.”

Pickup is a member of the National Association for Research and Therapy of Homosexuality, or NARTH, which describes itself as an organization that “offers hope to those who struggle with unwanted homosexuality.” NARTH calls the bill “a scientific and legislative travesty.”

“The fact that this legislation is solely directed at SOCE should be a red flag suggesting that ideological and political motivations may motivate backers of this legislation as much as any concern for consumers derived from the relevant science,” the group says.  “NARTH believes this effort, if successful, would set a dangerous precedence for the mental health professions, unjustly restrict client rights, and almost certainly invite legal action.”

Exodus International, a Florida-based Christian group that has “ex-gay” ministries and churches across the country, including about three dozen in California, declined to comment on the bill on Wednesday, saying the matter was "outside the scope of our ministry."

Other professional groups say they think the bill is well-intended but needs to be tweaked.

A coalition including the California Association of Marriage and Family Therapists, California Psychiatric Association, California Psychological Association, and the Association for Licensed Professional Clinical Counselors is seeking amendments to the bill.

“Our big concern is that the definition of sexual orientation change efforts is overbroad and too much is open to interpretation,” said Jill Epstein, executive director of the state marriage and family therapists association. “It could have a chilling effect on legitimate explorations of gender identity issues.”

Lieu says his office is working with the coalition to address the concerns.

He says public response to the bill has been overall very positive. But he’s also been the recipient of a steady stream of hate emails, phone calls and tweets, including one person who recently tweeted him: “I know that you are not a Christian, but God exists and you will not enter the kingdom of heaven for this.”

Lieu tweeted in response: “You do not decide, God does.”

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