After days of impassioned debate and stall tactics by Republicans, lawmakers in the state House found compromise Tuesday on Democratic legislation aimed at improving Colorado’s poor immunization rates.
The fight fizzled out as soon as Rep. Kyle Mullica, a Northglenn Democrat and sponsor of the vaccine bill, offered an amendment that would add a so-called “petition clause” to his legislation.
The clause means that once the legislature passes the measure, opponents would have until Sept. 12 to collect more than 124,000 signatures to put a question about whether to repeal it on the November 2022 ballot. Collecting the required signatures would block the vaccine law from going into effect at least until then.
The House passed the amendment nearly unanimously by voice vote after six hours of debate. Then lawmakers gave initial approval to the vaccine bill, Senate Bill 163. The vast majority of Republicans voted against the measure, but had given up fighting.
Immediately, opponents in the gallery booed and one woman shouted, “We will vote you out!”
Multiple GOP lawmakers read letters Tuesday during the debate from constituents who said they were parents whose children were injured by vaccines. Several of the notes threatened to make sure lawmakers were not re-elected if they did not try to kill the measure.
The legislation, which was passed by the Senate in February and still needs a final vote by the House, creates a standardized form to request an exemption from immunizations that are required to attend school. The legislation is expected to pass and Gov. Jared Polis is expected to sign it.
Under current law, parents who want to exempt their children from immunizations can write their request on a sticky note or even a napkin and hand it to their school office. With the change, parents would have to get the new standardized form signed by a doctor, nurse or pharmacist. As an alternative to the signed document, parents could turn in a certificate proving they watched a state-issued online educational video about vaccines.
Information from the exemption forms would go into a confidential database that public health officials could use in case of an outbreak. Parents could opt their children out of the database. Still, opponents of the bill said it amounted to a “government tracking system” and infringed on parents’ rights.
“The entire purpose of this bill is coercion,” said Rep. Mark Baisley, a Republican from Roxborough Park. “There is nothing else in the bill other than government coercion of citizen behavior.”
But Mullica, who is an emergency room nurse, repeatedly rejected the argument that the bill requires any child to be vaccinated.

“This idea that we are going to send somebody to your house and tie your child up and put a needle in their arm is just ludicrous,” he said.
“Let me say it again: It is an option, not a mandate.”
Republicans said it was unfair for Democrats, who control the House and Senate, to rush through such a controversial measure during the three-week lawmaking session, which comes after a two-month break because of the coronavirus pandemic. They were angry that Democrats scheduled the committee hearing on the bill for Sunday and that not everyone who was opposed was allowed time to testify.
“This whole process was unfair from the word go,” said Rep. Dave Williams, a Republican from El Paso County. “This whole thing has been kind of a train wreck.”
Mullica, in one of several passionate pleas at the microphone, asked: “Really? We shouldn’t be talking about improving our immunization rates in the middle of a pandemic?”
After days of debate, Mullica said he was bringing the amendment to add the petition clause in the spirit of working across the aisle.
House Minority Leader Patrick Neville, a Republican from Castle Rock who had previously vowed that the GOP would filibuster for days because of the bill, signaled that the minority party was giving in after the addition of the petition clause.

The clause gives citizens “one final say in this process,” he said. “This is really significant to a lot of people.”
Colorado’s vaccination rates are among the lowest in the nation, with 87.4% of kindergarteners vaccinated against measles, mumps and rubella. Across the nation, health officials say vaccinations are dropping fast during the coronavirus pandemic, presumably because families are putting off going to the doctor.
Opponents of the vaccine bill — who flooded the Capitol multiple times this session and last year when a similar bill failed — will need to collect more than 124,000 signatures from registered voters within 90 days of the legislative session ending in order to put a repeal on the ballot. Lawmakers are set to adjourn Friday.
The petition clause has worked before.
Republicans were successful after last year’s legislative session in gathering enough signatures to ask voters in November whether to repeal a law signing Colorado onto the national popular vote compact. It marks the first time since the Great Depression that Colorado voters will decide whether to repeal or affirm a law approved by the General Assembly and signed by the governor.
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In a normal year the repeal question would land on this year’s ballot, but because of the delayed legislative session in the wake of the coronavirus crisis, lawmakers are set to push the date back to 2022.
Colorado Sun staff writer Jesse Paul contributed to this report.