"Just as you don't have a right to yell 'fire' in a crowded theater you don't have a right not to vaccinate your child because of misinformation you may have received masking as a religious tenet," said State Sen. Brad Hoylman, a Manhattan Democrat and sponsor of the measure in the State Senate.

After an at times contentious debate – with protesters shouting down from a balcony – the Assembly narrowly approved the measure, by a 77-53 vote, one more than required to pass a bill. [Hours later, after some lawmakers had seen how the voting played out, the official roll call vote was amended after nightfall: 84 for and 61 against.]

The demonstrators, many with small children in strollers, erupted in a storm.

The State Senate, a couple hours later, with far less drama, OK'd it, by a 36-26 margin. Gov. Andrew M. Cuomo signed the bill into law Thursday evening.