SACRAMENTO, Calif. — Gov. Jerry Brown has signed legislation prohibiting a form of therapy aimed at changing a minor’s sexual orientation from gay to straight, the first law of its kind in the nation, officials said Sunday.

State Sen. Ted Lieu introduced the measure based on his belief that so-called conversion therapy is non-scientific and dangerous because in some cases patients have later committed suicide or suffered severe mental and physical anguish.

“No one should stand idly by while children are being psychological abused, and anyone who forces a child to try to change their sexual orientation must understand this is unacceptable,” said Lieu, a Democrat. “Gov. Brown should be commended for protecting LGBT youth by ending this type of quackery.”