Advocates praised Brown's action as an important victory "for a whole movement," The Sacramento Bee reported Tuesday.
While state law already protected transgender students from discrimination, the bill's sponsor, Democratic Assemblyman Tom Ammiano, said the bill clarifies students can't be barred from settings that are uniquely single sex, such as a men's basketball team or a women's locker room.
"The governor's signature represents an important victory, not just for my bill, but for a whole movement for the rights of transgender people," Ammiano said in a statement.
He noted in hearings on the bill, children testified passage of the law would mean "they no longer must hide who they are, nor be treated as someone other than who they are."
Republican Assemblyman Curt Hagman said he was "very disappointed" by Brown's signing of the bill, which had passed on a party-line vote.
Hagman charged the law "greatly compromised the privacy and rights of students throughout California."
Opponents of the measure had charged the bill would undermine parental choice and give prankster students a titillating peak inside locker rooms and bathrooms of the opposite sex.
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