Associated Press
Officials investigate the scene where a police officer was shot in the Lower 9th Ward of New Orleans, Tuesday, Jan. 26, 2016.
The US experienced another mass shooting on Sunday when a man entered a Waffle House in Nashville, Tennessee and opened fire, killing four people before a bystander heroically disarmed him.
In terms of strict state gun laws, Tennessee falls in the middle of the pack, according to the Giffords
The Giffords Gun Law Scorecard's methodology is based on nine different broad categories of laws, such as background checks, gun sales, and who can have a gun.
"We assign points to different policies ... and they're somewhat graduated based on the strength of the policy," Laura Cutilletta, legal director at the Giffords Law Center, told Business Insider.
"We also take away points if a state has something particularly dangerous, like letting guns in bars," Cutilletta said, adding that they then "add everything up, and we assign grades based on the points total."
"Probably the most important part is we compare that to death rate in every state," Cutilletta said, "and we find that there is a strong correlation between states with stronger gun laws and having lower gun death rates."
Here are the 10 states with the weakest gun laws in 2017: