NBC Bay Area reports on Professor John Donohue's research on gun violence and right-to-carry laws. 

More guns may in fact result in more violent crime, Stanford University researchers report.

Right-to-carry laws across the country are “associated with an increase in violent crime,” according to a review of data led by Stanford law professor John J. Donohue III.

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Donohue and his research colleagues looked at data from 1999 to 2010 that “suggests” right-to-carry laws may increase violent crime by 8 percent or more.