DENVER (CBS4)– A bill introduced in the state House would require the reporting of non-vaccinated students to the Colorado Department of Health and Environment. Currently those records are kept with the school.

“What this bill is not about is requiring more students to get vaccinations. It’s about who will keep charge of the records,” said Rep. Dan Pabon, a Democrat representing Denver.

A hearing at the state Capitol on Thursday was packed with parents who oppose the bill.

Christine Carter has four children and has had them vaccinated.

“I have the freedom to report what I’m going to do with my children or not,” said Carter. “I don’t think it’s the government’s business.”

The proposal opened an emotional debate about Colorado’s low vaccination rates. Colorado is one of 20 states that allow parents to claim any kind of personal opposition to required immunizations, and vaccine rates for some diseases are among the nation’s lowest.

Colorado passed a bill two years ago to have schools report vaccination rates. But for one in five Colorado kindergarteners, there was no immunization information on record for the 2014-15 school year.

Some of those who are opposed to vaccinations are fearful of the state obtaining the names of those who have opted out for fear it’s a step towards tracking them down.

Pam Long brought her son Josh to the hearing. She says he has a vaccine-induced brain injury.

“House Bill 1164 is designed to circumvent the law protecting privacy and bully people into every vaccine on the market,” said Long.

After Thursday’s marathon hearing the bill passed committee 7-6.