Last Updated Jun 30, 2015 2:40 PM EDT
UPDATE: California Gov. Jerry Brown signed the vaccination law on Tuesday. It takes effect next year.
SACRAMENTO, Calif. -- California lawmakers have passed a bill that would eliminate most exemptions from childhood vaccines and require the shots for nearly all children in public schools.
The state Senate gave final approval Monday afternoon with a 24-14 vote. Gov. Jerry Brown, a Democrat, signed it on Tuesday.
The law gets rid of California's personal belief exemption for immunizations, which allowed many families to opt out of vaccinating their children. While medical exemptions would still be granted to children with serious health issues, other unvaccinated children would need to be homeschooled.
It comes down to "No vaccine, no school," CBS legal analyst Rikki Klieman told "CBS This Morning." "This is a highly emotional issue on both sides."
Democratic Sens. Richard Pan of Sacramento and Ben Allen of Santa Monica introduced SB277 after an outbreak of measles at Disneyland in December infected over 100 people in the U.S. and Mexico.
Pan, a pediatrician, has said he worries about the spread of preventable illnesses. "We are seeing ever larger outbreaks of diseases like pertussis, whooping cough, measles, and we certainly don't want to see those diseases or others that are prevented by vaccines to be spread into our communities," he told CBS Sacramento.
"We have diseases that are showing up on public transit and restaurants and schools and shopping centers, theme parks, that is not what we want California to be," Pan said.
California joins Mississippi and West Virginia as the only states with such strict requirements.
The bill drew heated opposition from parents who have come by the thousand to protest at the Capitol in recent months.
Christina Hildebrand of the parents' group A Voice for Choice, which strongly argued against the bill, told CBS Los Angeles' KNX 1070 Newsradio it's an issue of civil liberties. "Realistically, this bill isn't about whether vaccinations are safe or not safe," said Hildebrand. "Our opposition is because it mandates vaccines, it takes away our children's fundamental right to an education."
But a mother whose then 4-month-old son contracted measles when he was too young to be vaccinated urged lawmakers to pass the bill. "I shouldn't have had to fear for his life," Ariel Loop told CBS Sacramento in April. "The idea of him or some other child dying from something as stupid as a fever or the complications of that in 2015 is just unnecessary."
Klieman said legal arguments against the bill may revolve around the right to public education, which she notes is "enshrined in the constitution of California." In order to enforce the vaccine requirement, "maybe what the state has to do is if it says you have to homeschool or you go into a private study group, maybe it's time for the state to put things online so kids are still schooled."
Amid all the protests and controversy, the bill passed both the Senate and the Assembly with bipartisan support.
The final version of the bill incorporated changes to make it easier for families to obtain medical exemptions, allowing doctors to use a family's medical history as a factor in their evaluation.
The authors also agreed to establish a grandfather clause, allowing students who currently claim a personal belief exemption to maintain it until their next vaccine checkpoint. Checkpoints occur in kindergarten and seventh grade.