More than a dozen parents and their developmentally disabled children attended the emotional bill-signing ceremony at PSE&G Children's Specialized Hospital in New Brunswick.
"I'm proud of this," Corzine said before signing the bill. "This is one of those things that will make a difference, not just for today and tomorrow but for long into the future."
Assembly Speaker Joseph Roberts, who championed the bill, agreed. He said the new law "mandates that health insurers do the right thing."
A federal Centers for Disease Control and Prevention study found 1 in 94 children in New Jersey have the genetic-based disorder, compared with 1 in 152 nationwide.
The legislation requires insurers to cover the cost of medically necessary treatments, such as physical, speech and occupational therapy, along with behavioral intervention. It caps insurers' liability at $36,000 a year.
Lawmakers sponsoring the bill faced resistance from health insurers and others who feared the new mandate would drive up health care costs for small businesses.
Roberts, however, said the opposite is true. With early diagnosis and treatment, he said, more children can receive mainstream educations, which cost about $13,000 per year per pupil, compared with about $50,000 a year for special needs students.
Christine Bakter, the mother of two autistic boys, said the bill lifts a financial burden off her family.
"I'm really tired of fighting," she said. "We have been paying insurance premiums all this time, and we haven't gotten the coverage we deserve."