A bill which would ban therapies that attempt to alter a young person's sexual orientation from gay to straight passed the California Senate on Wednesday.

The measure, approved on a 23-13 vote, was sponsored by Senator Ted W. Lieu, a Democrat from Torrance.

“The entire medical community is opposed to these phony therapies,” Lieu said in a statement after the vote.

“Being lesbian or gay or bisexual is not a disease or mental disorder for the same reason that being a heterosexual is not a disease or a mental disorder,” Lieu said. “The medical community is unanimous in stating that homosexuality is not a medical condition.”

Sponsoring the bill, which now heads to the Assembly, is Equality California, the state's largest gay rights advocate, and the National Center for Lesbian Rights.

“The California legislature has taken the right step in making sure that young people are protected from these unscrupulous therapists who are really engaging in therapeutic deception that is based on junk science,” Equality California's Rebekah Orr told CNN.

The National Association for Research & Therapy of Homosexuality (NARTH), a group which promotes the therapy, called the measure “another triumph of political activism over objective science.”

On its website, the group claims that passage of the bill would “likely increase harms to minors through its unintended consequences.” Parents, the group explained, would be forced to seek out therapy for their children from “unlicensed, unregulated and unaccountable religious counselors.”

“The vast majority of anecdotal accounts of harm to children from SOCE [Sexual Orientation Change Efforts] seem attributable to these types of counselors and to religiously oriented programs.”

Meanwhile, the Southern Poverty Law Center (SPLC) has filed an ethics complaint against a licensed Oregon therapist claiming he attempted to turn a 22-year-old gay student straight without his consent.

(Related: Dr. Robert Spitzer regrets 2001 study supporting “ex-gay” therapy.)