In the hours after the shooting Dec. 14, as anxious family members gathered inside a firehouse and waited for news, Malloy told them their loved ones were not coming home. He said later that he didn't think it was right for the families to wait for the victims to be formally identified.
Now, Connecticut joins states including California, New York, New Jersey and Massachusetts in having the country's strongest gun control laws, said Brian Malte, director of mobilization for the Brady Campaign to Prevent Gun Violence in Washington.
"This would put Connecticut right at the top or near the top of the states with the strongest gun laws," Malte said.
The legislation adds more than 100 firearms to the state's assault weapons ban and creates what officials have called the nation's first dangerous weapon offender registry as well as eligibility rules for buying ammunition. Some parts of the bill would take effect immediately after Malloy's signature, including background checks for all firearms sales.
Following a total of more than 13 hours of respectful and at times somber debate, the House of Representatives and the Senate voted in favor of the 139-page bill crafted by leaders from both major parties in the Democratic-controlled General Assembly. Both were bipartisan votes.
"I pray today's bill the most far-reaching gun safety legislation in the country will prevent other families from ever experiencing the dreadful loss that the 26 Sandy Hook families have felt," said House Majority Leader Joe Aresimowicz.
Colorado and New York also passed new gun control requirements in the wake of the Newtown shooting, in which a 20-year-old gunman used a military-style semi-automatic rifle.
Compared with Connecticut's legislation, which, for example, bans the sale or purchase of ammunition magazines holding more than 10 rounds, New York restricted magazines to seven bullets and gave owners of higher-capacity magazines a year to sell them elsewhere. Colorado banned ammunition magazines that hold more than 15 rounds.
But some lawmakers said they felt the legislation did not do enough to address mental health issues.
Gun rights advocates who greatly outnumbered gun control supporters in demonstrations held earlier in the day at the Capitol railed against the proposals as misguided and unconstitutional, occasionally chanting "No! No! No!" and "Read the bill!"
"We want them to write laws that are sensible," said Ron Pariseau, of Pomfret. "What they're proposing will not stop anything." How Conn. gun bill compares to new N.Y., Colo. laws
Connecticut's new gun control law, a response to the December massacre in Newtown that the governor signed into law Thursday, is among the strongest in the country. Here is a look at how its measures compare to laws passed this year in Colorado and New York:
Connecticut bans the sale or purchase of ammunition magazines holding more than 10 rounds. The law allows people to keep high-capacity magazines they already own if they're registered with the state by Jan. 1 but limits their use to the home and a shooting range.
New York restricted ammunition magazines to seven bullets and gave current owners of higher-capacity magazines a year to sell them out of state. Colorado banned ammunition magazines that hold more than 15 rounds.
ASSAULT WEAPONS BANS
Connecticut expanded its assault weapons ban, adding more than 100 firearms and requiring that a weapon have only one of several features in order to be banned.
New York also expanded its assault weapons ban. Colorado did not pass an assault weapons ban.
Connecticut requires universal criminal background checks for the sale of all guns, a measure that took effect immediately to close a loophole in private sales of rifles and shotguns. Background checks are also required to buy ammunition and magazines.
Colorado expanded background checks to private and online gun sales but did not require them to buy ammunition. New York expanded background checks to private gun sales and became the first state to require background checks to buy bullets.
DANGEROUS WEAPON OFFENDER REGISTRY
Connecticut created what officials called the first statewide dangerous weapon offender registry in the nation. Individuals who have been convicted of any of 40 weapons offenses must register with the state for five years after their release.
People involuntarily committed by court order to a hospital for psychiatric disabilities within five years are not eligible for a gun permit, up from one year under previous Connecticut law.
New York required mental health professionals to tell state authorities if a patient threatens to use a gun illegally.
Connecticut expanded the legal duty to securely store a firearm to cover situations where a resident of the premises poses a risk of personal injury to themselves or others.
New York requires locked storage of guns if you live with someone prohibited from them because of a crime, commitment to a mental institution or court protection order and made the unsafe storage of assault weapons a misdemeanor.