United States leads the world in mass shootings: New Study

When it comes to gun massacres, there are more public mass shootings in the United States than in any other country in the world, according to a new study.

Between 1966 and 2012, there were 90 mass shootings in the US, where there is nearly one firearm for every American.

The 90 mass shootings in the country are nearly a third of the 292 such attacks globally for that period. While the US has 5% of the world's population, it had 31% of all public mass shootings.

Mass shootings are defined for the study as having four or more victims and don't include gang killings or slayings that involve the death of multiple family members.

"People have been a little surprised by these statistics," CNN quoted Adam Lankford, an associate professor of criminal justice at the University of Alabama, who did the analysis. Lankford presented his work at the American Sociological Association's annual conference last weekend and says it's the first research of its kind to do a global comparison.

Lankford combed through the records of every incident and found a few common factors that set the US incidents apart from the rest of the world's. In the US, people have a greater chance of dying in mass shootings if they are at work or at school. Overseas, these incidents typically happen near military installations.

In more than half the American cases, the shooter had more than one firearm. In global incidents, the shooter typically had only one gun. And in the US, there are 6.87 victims on average per incident. In the other 171 countries Lankford studied, the average was 8.8 victims per incident.

The incidents of mass attacks tripled from 2011 to 2014, according to a new analysis by the Harvard School of Public Health and Northeastern University. The Harvard research showed that public attacks in that time occurred every 64 days on average. During the previous 29 years, they happened every 200 days on average. In contrast, the overall US homicide rate and rate of gun violence have dropped significantly over the past two decades.

Some researchers also believe these mass killings can be contagious. The copycat phenomenon is more acute in the US because guns are more accessible than in other countries, Lankford said.

The United States has more guns than any other country in the world. There are an estimated 270 million to 310 million firearms in circulation in America. With the American population at 318.9 million, that breaks down to nearly one firearm for every American. 

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