Beginning Sunday, Coloradans will have to wait at least three days after purchasing a firearm to receive it.

The new state law requires gun sellers to wait three days to deliver a gun to a purchaser, or wait for an approved background check if the check takes longer than three days. Colorado legislators passed the law in April.

Proponents say delaying access to firearms is meant to prevent impulsive acts of violence, including suicides. Last year, 690 Coloradans committed suicide with firearms, accounting for more than half of suicides in the state. The year before, Colorado had the sixth-highest suicide rate in the country.

“I have experienced firsthand how a ‘cooling off’ period can save someone’s life when they are in crisis and trying to purchase a firearm,” said Rep. Judy Amabile, D-boulder, who sponsored the waiting period bill.

“My son is still with us today because his background check was delayed when he went to a local gun store, and I am forever grateful he did not have instant access to a firearm that day.”

Waiting period laws in other states have resulted in a 7% to 11% reduction in gun suicides, and a 17% reduction in gun homicides, according to a 2017 study.

Opponents argue the new law violates the constitutional right to bear arms. Rocky Mountain Gun Owners sued to block enforcement of the three-day waiting period, but a judge declined to bar the law in August.

“Gun owners’ rights are being ravaged in the Colorado Legislature,” said Taylor Rhodes, executive director of Rocky Mountain Gun Owners, when announcing the lawsuit. “When a single mother is being harassed by a violent, abusive former partner, the Democrats at

the Capitol think it is fine to make her wait at least three days to defend herself and her baby.”

A second new law will take effect Sunday. The measure allows gun violence victims to sue firearm manufacturers and dealers by removing immunity protections. It also repeals a state law that makes gun violence victims pay the company’s legal fees in dismissed cases.

The law is named after Jessica Redfield Ghawi. Her parents, Sandy and Lonnie Phillips, sued gun dealers for selling ammunition without a background check to the man who murdered 12 people at the Aurora theater shooting in 2012, including Ghawi. The Phillips sold their house and declared bankruptcy after having to pay around $200,000 in legal fees to the dealers.

“Colorado used to be home to one of the most punitive laws against gun violence survivors in the country, laws that shielded them from accountability and needed to be changed,” said Sen. Sonya Jaquez Lewis, D-longmont, sponsor of the bill. “This new law will level the playing field by removing those extra protections and allowing legitimate lawsuits to move forward.”