THE NEW LAW

AT A GLANCE

— Bans the sale or purchase of ammunition magazines holding more than 10 rounds

— Previously owned high-capacity magazines must be registered with the state by Jan. 1

— Expands assault weapons ban, adding more than 100 firearms

— Requires that a weapon have only one of several features in order to be banned

— Requires universal criminal background checks for the sale of all guns

— Background checks are also required to buy ammunition and magazines

— Anyone convicted of any of 40 weapons offenses must register with the state for five years

— People involuntarily committed for psychiatric disabilities within five years are not eligible for gun permit

— Expanded the legal duty to securely store a firearm where a resident poses a risk

Gov. Dannel P. Malloy, who four months ago broke the news to shocked parents that their children had been slaughtered in a Connecticut elementary school, signed into law Thursday sweeping new restrictions on weapons and large capacity ammunition magazines similar to the ones used by the man who gunned down 20 child and six educators in the massacre.

Alongside family members of some of the victims of the shooting at Sandy Hook Elementary School, Malloy signed the bill hours after the General Assembly approved the measure to give the state some of the toughest gun laws in the country.

“This is a profoundly emotional day for everyone in this room,” the governor said. “We have come together in a way that few places in the nation have demonstrated the ability to do.”

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.

In the legislature, leaders waited to unveil gun legislation until they struck a bipartisan deal that they say shows how the parties can work together in Connecticut and elsewhere. They touted the package as a comprehensive response to Newtown that also addresses mental health and school security measures, including the creation of a new council to establish school safety standards and the expansion of circumstances when someone’s mental history disqualifies him or her from obtaining a gun permit or other gun credentials.

“We did our job. We did it together,” said House Minority Leader Lawrence Cafero Jr. “We did the best we could and I think we did a good thing.”