California law already prohibits discrimination against transgender students. But Democratic Assemblyman Tom Ammiano is backing a bill that would ensure those students can play on sports teams and use facilities based on the gender they identify as and not on their biological sex.
He says the law will have a wide impact.
"This is not a small group," he says. "The group's been invisible. The group's been maimed and murdered and marginalized, but this is not a small group."
Republican Assemblyman Curt Hagman says he reluctantly voted against the measure. On the Assembly floor he called the bill impractical.
"It's one thing to play on a different team," he says. "It's another thing to go into the locker rooms, change, shower, those type of things, when already a 11, 12, 13-year-old is already kind of nervous about all that stuff in a public setting."
But Ammiano, who is gay, says that argument falls flat.
"Because someone is uncomfortable is not a reason to discriminate," he says. "I can walk into rooms in many of your districts and I know your constituents would be uncomfortable with me."
Ammiano says Los Angeles and San Francisco schools are already working to accommodate transgender students. He says his bill is meant to give other schools districts some direction.
The bill was approved in the Assembly and now moves to the Senate.