Daniel Webster, Director of the Johns Hopkins Center for Gun Policy and Research, led a study that examined gun deaths in the state of Missouri after the state repealed its permit-to-purchase handgun law in 2007. The researchers found that the state’s murder rate increased after the repeal.

The number of murders involving handguns increased an average of 60 more people per year after the state legislature allowed residents to purchase guns from unlicensed sellers without undergoing a background check. From 2007 to 2012, surrounding states’ murder rates hardly increased and the country’s murder rate declined five percent.

“This study provides compelling confirmation that weaknesses in firearm laws lead to deaths from gun violence,” said Webster. “There is strong evidence to support the idea that the repeal of Missouri’s handgun purchaser licensing law contributed to dozens of additional murders in Missouri each year since the law was changed.”

According to statistics released by the Center for American Progress, as of 2010, Missouri had the fourth-worst gun-murder rate in the United States, 56 percent higher than the national average. There are 5.6 gun homicides per 100,000 people in Missouri, but the nation tallied only 3.6 per 100,000. The same year, 82 children aged 0-18 years were killed by gun violence in the state.

The occurrence in Missouri reflected what has been happening in other states with high gun-murder rates. The three worst states for gun violence are Alabama, Alaska, and Louisiana at number one. These states, and most others like them, have one main striking similarity lenient gun laws.

In Louisiana, state law allows the purchase of assault weapons and high-caliber rifles. Also, there is no waiting period for handgun purchases. There are 9.53 gun-murders per 100,000 people in Louisiana every year. These statistics are contradictory to the Republican, gun-loving notion that “more guns equals safer streets.” Eight of the 10 states with the highest amount of gun violence governors are Republican.

Further linking loosened gun laws to gun violence, the study used other forms of violence as a control study. “That upward trajectory did not happen with homicides that did not involve guns,” said Webster. The fact that non-gun murders did not increase illustrates further proof that gun laws actually prevent gun violence.

Currently, there are only 15 states that require background checks on purchases from unlicensed sellers, and there are over 300 million guns in circulation in America, nearly one for every American man, woman, and child.

Josh is a writer and researcher with Ring of Fire. Follow him on Twitter @dnJdeli.