Attorneys who filed a federal lawsuit against a new law in New York that bars parents from seeking religious exemptions to vaccines, which are required for their children to attend school or daycare, have dropped their legal challenge against the state, court filings show.

That doesn't leave the law unchallenged; attorneys still have a lawsuit against the measure in state court, where a motion to put the statute on hold is under consideration.

The federal case was dropped by the attorneys who brought it just days after their motion to block the new law, through either a preliminary injunction or "stay-put order," was denied by a federal judge in Brooklyn on Monday.

The attorneys on the federal case were Robert F. Kennedy Jr., who's been a vocal skeptic of  vaccine safety, and Kimberly Mack Rosenberg, a partner at Bouer Law, a Manhattan firm that typically specializes in insurance issues.

Court filings show that Kennedy and Rosenberg dropped the federal case Thursday. That's allowed under a section of federal court rules that allows a lawsuit to be voluntarily dismissed by the plaintiffs before the target of the litigation files an answer to the challenge or moves to dismiss it.

The defendants named in the lawsuit—Gov. Andrew Cuomo, New York Attorney General Letitia James, State Education Commissioner MaryEllen Elia, the State Education Department and another state education official—had not done so, as of this week.

By Friday morning, the case was marked as terminated from the U.S. District Court for the Eastern District of New York, according to the docket.

James said in a statement she was pleased the case had been terminated and expected the same outcome in other legal challenges to the law.

"Vaccines ensure the health and safety of our children, our families, and our communities," James said. "This law will help protect New Yorkers from experiencing any additional public health crises, which is why we vigorously defended it."

Rosenberg confirmed Friday that the case had been dismissed, but said that their short-lived lawsuit, which was filed less than a month ago, had already had a positive impact for the families she was representing in court.

"We are looking at additional avenues to address issues regarding children with [individualized education plans], so, while this specific case has been dismissed, work is continuing," Rosenberg said. "We remain committed to these issues for all children in New York, not only children with IEPs."

They were denied a motion to block the state from enforcing the new law in a decision earlier this week by U.S. District Judge Allyne Ross of the Eastern District of New York.

The law was among the most controversial measures approved by the state Legislature earlier this year, so much so that it only passed by a handful of votes in the State Assembly. It removed the option for parents to seek nonmedical exemptions to vaccines for their children to attend daycare or school, regardless of whether that institution is public, private or parochial.

It was sparked by a major outbreak of the measles in areas of Rockland County and New York City over the past year, largely in areas where parents have foregone vaccinating their children.

The case brought in federal court against the law took a very different litigation strategy than the action in state court. The federal lawsuit, filed in late July, argued that the statute conflicted with the Individuals with Disabilities Education Act, a federal law that essentially requires that children with disabilities have access to a free public education.

Federal funding is provided through the law for local school districts to provide services to students with disabilities. States are then responsible for ensuring that the law is enforced to provide those children with a free appropriate public education.

But the new law, the attorneys had argued, denied children with disabilities access to an education by barring them from attending school if they don't receive the required vaccines. Those children, instead, have to be homeschooled under the law.

Rosenberg said Friday that, before their lawsuit, it wasn't clear whether school districts would be required to provide services to children with disabilities who were homeschooled because they weren't vaccinated. That changed when, in court filings, the state clarified that those services would be available to students with disabilities, regardless of their vaccination status.

"Although we continue to maintain that services to these children are mandated under the IDEA to be provided in schools and educational settings … we are heartened by the fact that these children should be able to access some of their rights under IDEA as litigation and other avenues are pursued," Rosenberg said.

Ross had confirmed as much in her decision earlier this week. She ultimately rejected their request to put the law on hold, saying it wasn't the state that was preventing those children from attending school, it was the parents who chose not to have them vaccinated.

"Though plaintiffs disagree with the legislature's judgment, New York was entitled to determine that the religious exemption was endangering all students, and that the elimination of the exemption was the best way to protect the needs of all children—including children with disabilities," Ross wrote.

The lawsuit in state court, brought by Kennedy and attorney Michael Sussman, has argued that the new law doesn't square with the religious freedom rights of certain families.

They've also argued that the state didn't take advantage of the options it had to respond to last year's measles outbreak before the Legislature decided to approve the new law. Those were things like isolating unvaccinated children, and executive action by state health officials.

Attorneys in that action argued earlier this month for a preliminary injunction against the law before Albany County Supreme Court Justice Denise Hartman. They claimed that, if the law is not blocked, thousands of children who were previously granted religious exemptions won't have access to an education because homeschooling isn't an option for everyone.

Hartman is expected to hand down a decision on the motion in the coming weeks, if not days, so that parents can know what course of action to take as the school year begins.

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