DENVER (CBS4) – Colorado Gov. Jared Polis signed a controversial gun control measure into law on Friday. The Red Flag law will allow authorities to take guns from people determined to pose a threat to themselves or others.

Relatives or officers would have to petition a court to have the guns removed, which could be extended for up to 364 days.

The gun owner would then have to prove he or she no longer poses a risk in order to get the firearms back.

As Polis signed the bill into law, a wave of emotion washed over Rep. Tom Sullivan.

“I struggle with the price we paid to get to where we are today,” said Sullivan.

Sullivan’s son, Alex, was killed in the Aurora theater shooting.

“Three hundred and fifty one Fridays since Alex was murdered,” Sullivan began, wearing his son’s leather bomber jacket at the signing ceremony for the bill he sponsored.

“Being the parent of a murdered child, everything is stunted,” Sullivan said, prompting knowing, tearful nods from several other shooting survivors standing behind him. “I am elated, believe me. It just can’t come out because there is just too much work in front of us to get done.”

Alex Sullivan was celebrating his 27th birthday at the theater. Tom Sullivan, elected to the House in November, has devoted his life since Aurora to counseling survivors of other mass shootings around the country and campaigning for gun control.

The law is named after Douglas County Sheriff’s Deputy Zackari Parrish III, a 29-year old husband and father who was killed on New Year’s Eve 2017 by a man who had exhibited increasingly erratic behavior.

Parrish’s boss, Douglas County Sheriff Tony Spurlock, and Boulder County Sheriff Joe Pelle attended. Pelle’s son, a Douglas County sheriff’s deputy, was wounded in the shooting that killed Parrish.

Pelle said he was working with Spurlock and other law enforcement chiefs to develop protocols for executing protective orders safely.

Some government and law enforcement leaders from across the state say they either are against it or won’t enforce it.

Weld County Sheriff Steve Reams spoke to CNN.

“In my mind going in and having a confrontation with someone to take their firearms, but not deal with the person just creates a bigger issue,” Sheriff Reams said. “I would rather risk violating a court order than violating someone’s constitutional rights.”

RELATED: Weld County Now A Second Amendment Sanctuary County, Officials Say

The bill was introduced after Douglas County Sheriff’s Deputy Zack Parrish was killed on New Year’s Eve in 2018. He was trying to take a man in for a mental health hold.

Colorado would become the fifteenth state with a “Red Flag Law.”