With lawmakers preparing to vote on a bill blocking parents from skipping vaccinations for their children, prominent vaccine skeptic Robert F. Kennedy Jr. arrived at the Sacramento screening of a film linking autism to the vaccine preservative thimerosal and warned that public health officials cannot be trusted.

“They can put anything they want in that vaccine and they have no accountability for it,” said Kennedy, who walked onto and left a Crest Theater stage to standing ovations, of the federal Centers for Disease Control and Prevention.

Wednesday afternoon will see the first hearing for a bill eliminating the personal belief exemption parents can cite in order to avoid vaccinating their kids. Senate Bill 277 was prompted by soaring exemption rates in some schools districts and outbreaks of long-dormant diseases like measles and whooping cough.

Kennedy has credited the film Trace Amounts with helping to persuade lawmakers to halt a vaccination measure in Oregon. Advocates offered free Trace Amounts tickets to every California lawmaker, visiting offices in the State Capitol on Monday to drop them off. Three rows cordoned off for lawmakers sat empty on Wednesday evening, though some staff members attended.

The overwhelming scientific consensus supports vaccine use and dismisses any serious side effects. Multiple studies have rejected any link between the mercury-containing chemical thimerosal and autism. Nevertheless, vaccine manufacturers have removed thimerosal from nearly all childhood vaccines (some influenza vaccines are the exception) and a California bill further barred thimerosal content.

In light of those facts, SB 277’s author called Kennedy’s continued activism disingenuous.

“I think it is dangerous that he is spreading misinformation about something that’s very important for public health,” Sen. Richard Pan, D-Sacramento, a pediatrician, said in an interview. “Autism rates have continued to rise even though we are not using thimerosal in vaccines for children,” he added. “We still haven’t figured out exactly what causes autism. We do know it’s not vaccines.”

But some parents fear information about the hazards of vaccines has been suppressed, largely because of what they call the pharmaceutical industry’s influence over health officials. Many parents believe their children have been damaged by vaccines. When Kennedy asked the crowd of a few hundred viewers how many parents had a child injured by vaccines, numerous hands went up.

“They get the shot, that night they have a fever of a hundred and three, they go to sleep, and three months later their brain is gone,” Kennedy said. “This is a holocaust, what this is doing to our country.”