TRENTON - (AP) -- Calling the federal agency that makes recommendations on vaccines a "sock puppet" for that industry, Robert Kennedy Jr. spoke out Monday against making it harder for parents to exempt their children from vaccinations.

Kennedy, the nephew of President John Kennedy and son of former U.S. Attorney General Robert Kennedy, joined groups that oppose school-attendance vaccination requirements for a news conference in the New Jersey Statehouse in Trenton. The Legislature is considering bills that would tighten rules for vaccine exemptions.

Kennedy said he supports using vaccines and had all six of his children vaccinated, but he said the pharmaceutical industry profits immensely from the government's recommendations. The Food and Drug Administration licenses vaccines, and then the Centers for Disease Control and Prevention recommends to doctors what vaccines to use, who should get them and when to administer them.

He said school-attendance rules mean that vaccines are the only product Americans are required to consume and that Congress protected pharmaceutical companies from liability for problems stemming from them in the 1980s.

"All of the studies show the primary reason people don't vaccinate -- the primary reason -- is mistrust of the regulators," he said. "The solution to this problem, to the extent that it's a problem in New Jersey, is to restore the regulatory process, not to compel people to do something that they may feel they have very good reason not to do."

Lawmakers are pushing bills that allow parents to exempt their children from vaccine requirements only for medical and religious reasons. Under current law parents can cite a general religious objection, but the new legislation requires parents to furnish either a letter from the child's doctor showing a medical reason against vaccination, or a notarized letter demonstrating that inoculation violates "bona fide religious tenets."

The issue gained attention earlier this year after a major measles outbreak was linked to an infected visitor at Disneyland.

Then Gov. Chris Christie suffered a round of scathing attacks after making comments on the issue during a trip in the United Kingdom. He said that while he and his wife vaccinated their children, parents should have some "measure of choice in things as well."

Kennedy is a liberal radio talk host and activist and editor of a book called "Thimerosal: Let the Science Speak." The chemical is a mercury-containing preservative that has been removed from routine childhood vaccines in the U.S.

He did not focus on the New Jersey legislation during the news conference, but he was scheduled to meet with a number of lawmakers in Trenton on Monday about their bill.