Sunday evening, a single gunman fired on a crowd attending a country music festival outside Mandalay Bay Resort and Casino, killing at least 59 and injuring at least 527. Just 16 months ago, a man killed 49 and injured 58 at the Pulse nightclub in Orlando, Florida. 

Mass shootings such as these are by no means rare events, and each time one occurs it brings the same topic into our national discourse: gun legislation. 

Gun laws across the country vary widely, and according to legal information site FindLaw.com, Michigan’s regulations are somewhat middle-of-the-road. But gun legislation is far from simple. 

“There are many, many areas of gun law,” Dr. April Zeoli, associate professor at MSU’s School of Criminal Justice, said. Zeoli is an expert on certain areas of firearm legislation. 

“From prohibiting certain people and controlling sales of guns, but there are also laws on firearms in public places, concealed carry, guns in vehicles, dealer regulations. So it really is a very, very, very large field.” 

According to the Law Center to Prevent Gun Violence, Michigan requires background checks to purchase guns and prohibits the sale or ownership of automatic weapons and machine guns, except in the case of people permitted to do so by the Federal government. The state does not prohibit the “transfer or possession” of assault weapons, 50 caliber rifles, or large capacity magazines. 

When it comes to background checks for gun purchases, requirements vary from state to state, Zeoli said.

“The Federal government has a law that if you buy from a licensed firearms dealer, you have to get a background check,” Zeoli said. 

These background checks are performed using a system called the National Instant Criminal Background Check System, known as NICS. 

“The NICS system will look for mental health records, it will look for prohibited drug abuse, substance abuse records,” Zeoli said. “It will look for felonies that prohibit, domestic violence and misdemeanor crimes, domestic violence restraining orders. And if any of those prohibited categories, including a couple others I didn’t mention, like those who have been dishonorably discharged from the military or those who have renounced U.S. citizenship. If any of those records pop up, you are not allowed to buy from a licensed dealer. And that licensed dealer who runs a background check will know that and won’t sell the gun to you.”

But there’s a loophole in that federal law: private citizens selling guns aren’t required to run a background check.

“If I live in a state like Ohio, I can be denied purchase of a gun by a licensed dealer because some kind of prohibiting criminal offense popped up on my record check,” Zeoli said. “But then I can just go to a private citizen who is selling a gun and get that gun without a background check. Private citizens who sell firearms don’t have to do a background check on somebody to sell them the firearms. They don’t have to inquire whether you are prohibited.” 

However, Michigan doesn’t have that loophole due to the “permit-to-purchase” system. 

“If someone wants to buy a handgun in Michigan, they have to get a permit to buy the handgun,” Zeoli said. “You go to local law enforcement or a government official, you say you want to buy a handgun, they run the criminal background check and determine whether you are qualified to own a handgun or have had those rights limited due to some kind of criminal offense. So if you are able to purchase a firearm, they give you a permit. You have to have a permit, it doesn’t matter who you’re buying from. It could be a federally licensed dealer, it could be a gun store or some place that sells guns like Walmart or Cabela's or wherever, or a private citizen.”

Evidence shows that permit-to-purchase laws work, Zeoli said. In the past they've been implemented in other states such as Missouri and Connecticut. 

“Researchers found that this permit-to-purchase system is correlated with lower homicides and lower rates of gun crimes,” Zeoli said.

But in 2007, when Missouri repealed its permit-to-purchase law, researchers got an opportunity to see how those rates would be affected by a change in legislation. In a 2014 study published in The New York Academy of Medicine’s Journal of Urban Health, researchers found that firearm homicides increased by 23 percent after Missouri repealed its permit-to-purchase law in August of 2007. 

“Michigan does really well on that front by implementing these restrictions across the board,” Zeoli said.

But when it comes to laws regarding assault weapons like the ones used by the Las Vegas shooting suspect, Michigan is more lax. According to the Law Center to Prevent Gun Violence, Michigan has no laws on the books concerning assault weapons in any way. In the now-defunct 1994 Assault Weapons Ban, the justice department characterized assault weapons as “semiautomatic firearms with a large magazine of ammunition that were designed and configured for rapid fire and combat use.” Subsequent legal definitions vary widely. 

In October of 2016, in the wake of the deadly shooting at the Pulse nightclub in Orlando, Florida, Michigan House Democrats introduced a bill intended to ban assault weapons in Michigan. The bill defined assault weapons as “a semiautomatic pistol or semiautomatic or pump-action rifle that is capable of accepting a detachable magazine.”

A spokeswoman for the National Rifle Association, or NRA, at the time said banning assault weapons would do nothing to alleviate crime, and a Republican legislator called the bill “dead on arrival.” 

Michigan is also an open-carry state, meaning that it is legally permissible to carry a firearm in public as long as the firearm is not concealed and is carried with lawful intent. Specific restrictions dependent on location apply. For example, it is illegal to carry a concealed weapon on the premises of a bank, a church, a sports stadium, or a hospital. 

Carrying a firearm on campus is not allowed by MSU policy, though state law does not prohibit firearms on college campuses. The rule is stated in the Spartan Life Handbook as follows:

Except as permitted by state law regulating firearms, no person shall possess any firearm or weapon anywhere upon property governed by the Board. Persons residing on property governed by the Board shall store any and all firearms and weapons with the Department of Police and Public Safety. 

According to reports, the Las Vegas shooter used a device called a "bump stock" to enable the rifles used in the shooting to fire as if they were fully automatic instead of semiautomatic. These devices are legal under federal law, and there are no specific prohibitions against them in Michigan law.