After the Sandy Hook Elementary School massacre in Newtown, Conn., left 26 dead in December 2012, lawmakers across the U.S. made attempts to prevent similar horrors.

Five years later, the results are uneven at best.

In the wake of the shooting, perpetrated by 20-year-old Adam Lanza, U.S. Senate Democrats introduced a bill to create a federal ban on assault rifles – reviving an old expired 1994 law that prohibited the manufacture for civilian use certain semi-automatic firearms and large capacity ammunition magazines.

Opponents argued that the previous law prohibiting assault fires made no impact on crime, while advocates -- namely U.S. Sen. Dianne Feinstein, D-Calif. -- said the 1994 law “was effective at reducing crime.”

But as fact-checkers pointed out, both sides used selective statistics from a series of studies that, in reality, found the impact “mixed.”

Also introduced: A bipartisan bill called the Manchin-Toomey Amendment, aimed at ordering universal background checks in all states for all firearms.

But neither measures passed a Democrat-controlled Senate, leaving lawmakers in Washington without a response to one of the deadliest school shootings to date.

Following the vote on federal background checks, National Rifle Association chief lobbyist Chris Cox said the amendment “would have criminalized certain private transfers of firearms between honest citizens, requiring lifelong friends, neighbors and some family members to get federal government permission to exercise a fundamental right or face prosecution,” USA Today reported.

He added: "As we have noted previously, expanding background checks, at gun shows or elsewhere, will not reduce violent crime or keep our kids safe in their schools."

Compromises under Trump

Since the election of President Donald Trump, gun-control advocates have been skeptical of seeing legislation on firearms in the near future -- largely because Trump was backed by the National Rifle Association during the 2016 presidential election.

The Las Vegas gunman opened fire from the 32nd floor of the Mandalay Bay hotel suite, leaving 58 people dead and more than 500 injured. (AP)

But the Trump administration has shown a willingness to compromise. After the Oct. 1 Las Vegas shooting that left 58 people dead and more than 500 injured, there were calls to outlaw the so-called “bump stock” devices that convert semi-automatic rifles to automatic.

While the NRA initially was open to “federal review” of such devices, it has since come out against any attempts to legislate a ban against it. “The bill (aimed at banning bump stocks) goes beyond banning bump stocks, it could ban things like aftermarket triggers, bolts, or other components,” the NRA’s Twitter account wrote in October.

And yet, the Department of Justice (DOJ) and Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) announced last week that it started a review of the legality of bump-fire stocks.

"The Department of Justice has the duty to enforce our laws, protect our rights, and keep the American people safe," Attorney General Jeff Sessions said in a statement. "Possessing firearm parts that are used exclusively in converting a weapon into a machine gun is illegal, except for certain limited circumstances. Today we begin the process of determining whether or not bump stocks are covered by this prohibition.”

At the same time, gun-rights advocates scored a victory this week after a bill making concealed-carry gun permits valid across state lines passed the House. It now faces a tough Senate battle as it needs the votes of at least eight Democrats to make it to Trump's desk for a signature.

State-led efforts

A memorial for the victims of the 2012 Sandy Hook shooting.

But as the attempts to legislate in Congress failed, local politicians in some states have taken the task to their state-level chambers, where strides were made to enact some form of gun control.

Around 210 measures aimed at limiting access to firearms were enacted since the Sandy Hook shooting, according to the Giffords Law Center to Prevent Gun Violence. Four states – Washington, Nevada, Colorado and Delaware – have passed legislation to create background checks for gun buyers following the massacre. A number of states have also widened their existing gun control laws.

In Connecticut, five years since the shooting in Newtown, state lawmakers made multiple changes to the gun laws. They broadened the definition of assault weapons – banning more than 150 gun models – and prohibited the sale of large capacity gun magazines, New England Public Radio reported. The state also has a registry of weapon offenders and universal background checks.

Ron Pinciaro, executive director of Connecticut Against Gun Violence, said the sweeping changes to gun laws in the state made a massive impact on the homicide rate. “If you look the homicide rate, I think it worked out that there were 92 gun homicides per year in Connecticut on average. Last year – 2016 – there were 53.” Pinciaro told the radio station.

No easy answers

But measures focused on restricting firearm access after a mass shooting fail because only a small number of people die in such instances, making it difficult to convince the public as an overwhelming majority of shooting deaths occur in suicides, gang-related shootings and in domestic violence cases.

“Far more people were killed in these ways than in mass-shooting incidents, but few of the popularly floated policies were tailored to serve them,” wrote Leah Libresco, a statistician and former writer for data-journalism site FiveThirtyEight, after the Las Vegas shooting.

The statistician said there are no easy answers regarding gun violence and most suggestions by lawmakers would not tackle the less-shocking yet more-prevalent gun deaths. Two-thirds of gun deaths in the country are suicides, according to her, while other gun deaths consist of young men being killed “at the hands of other young men, often related to gang loyalties or other street violence.” In addition, 1,700 women are murdered every year, mostly as the result of domestic violence.

“I can’t endorse policies whose only selling point is that gun owners hate them. Policies that often seem as if they were drafted by people who have encountered guns only as a figure in a briefing book or an image on the news.