As the debate on guns heats up, there is one thing we can all be certain of: Lots of statistics will be thrown about.

On this blog, we've already pointed to a Department of Homeland Security study on commonalities in mass shootings.

Today, we'll point you a study commissioned by Mayors Against Illegal Guns. As the name implies, the group led by New York City Mayor Michael Bloomberg is advocating for stronger gun control laws.

The group looked at "mass shootings" (meaning shootings where at least four people were shot and killed) in 25 states. They looked at 43 shootings that occurred between January 2009 and January 2013.

As the white paper notes, some of the findings defy "conventional wisdom." Among them:

-- "Mass shootings represent a small share of total U.S. firearm homicides. Less than one percent of gun murder victims recorded by the FBI in 2010 were killed in incidents with four or more victims."

-- "Assault weapons or high-capacity magazines were used in at least 12 of the incidents (28%). These incidents resulted in an average of 15.6 total people shot — 123% more people shot than in other incidents (7.0) and 8.3 deaths — 54% more deaths than in other incidents (5.4)."

Another interesting find is that most of the cases studied here (40 percent) were the result of domestic violence. If you remember, the DHS study, which looked at the 29 deadliest mass shootings since 1999, it found most of them occurred at the workplace.

We'll leave you with one more statistic. During his testimony on the Hill, NRA Executive Director Wayne LaPierre said that "fatal firearms accidents are at the lowest level in 100 years."

Politifact took a look at the stats behind that statement. They looked at the stats published by the National Safety Council. Indeed, it found, the number of unintentional deaths form firearms has plummeted from the early 1900s.

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