Eight states have passed laws allowing concealed carry on college campuses. But in a new report, Johns Hopkins researchers argue that legally armed citizens don't prevent mass shootings and may actually lead to more violence.
Supporters of campus carry laws say individuals should have the right to protect themselves.
But the authors examined previous studies on gun violence and found armed citizens rarely stopped a mass shooting or reduced the number of victims.
A study cited in the Johns Hopkins report found only 2 percent of college campus shootings from 2013 to 2015 involved a shooter "on a rampage." Nearly half of the shooting incidents were fights that escalated to gun violence.
Allowing guns in the hands of college students may also heighten other risks. The report points to binge drinking, higher suicide rates and risk-taking attitudes as examples of why college campuses aren't the place for more guns.
The Johns Hopkins report argues that even if permit-holders could protect against mass shootings, the net effect of more guns on campuses would be more deaths, injuries and threats of gun violence.
Related: Also see the states with the toughest gun laws:
States with the toughest gun laws
States with the toughest gun laws
National Rifle Association's (NRA) annual meetings and exhibits show in Louisville, Kentucky, May 21, 2016. (Reuters)
#24. West Virginia
Score: 18 Grade: D-
West Virginia may rank low in terms of overall gun control, but in 2015 Democratic Gov. Earl Ray Tomblinvetoed a bill that would have allowed people to carry concealed weapons without a permit.
Score: 19.5 Grade: D-
The relatively lax firearm laws in Indiana have led some to link them to gun violence in Chicago.
#22. New Hampshire
Score: 20.5 Grade: D
New Hampshire requires handgun dealers to obtain a state license, but does not extend the rule to dealers of rifles and shotguns.
Score: 21.5 Grade: D
Nebraska differs from many states in that it gives local jurisdictions some control over firearm regulations.
Score: 22 Grade: D
Following the Virginia Tech shooting in 2007, the state took greater measures to report mental health records and prohibit sales of firearms to any person who has been "adjudicated as a mental defective."
Score: 24 Grade: D
Ohio does not prohibit the sale of assault weapons nor limit the number of firearms that may be purchased at one time.
Score: 25 Grade: D
In a major blow to gun control advocates, Republican Gov. Scott Walkerrepealedthe state's mandatory 48-hour waiting period for handgun purchases in 2015.
While Colorado requires licensed firearms dealers to process background checks, it does not impose limits on the number of firearms that may be purchased at one time.
Score: 30 Grade: C
Michigan gun control laws require firearm owners to report handgun purchases and theft of any firearm.
Score: 31 Grade: C
Oregon greatly strengthened its firearm regulations in 2015 when it enacted laws requiring background checks for all firearm purchases.
Score: 35 Grade: C
Compared to other solidly Democratic states, Pennsylvania's gun control laws are relatively lax, with no requirements for firearm owners to obtain licenses or register their weapons.
Score: 36.5 Grade: C
Although federally licensed firearms dealers must initiate background checks, Minnesota does not require private sellers to do so.
Score: 47.5 Grade: B-
Washington requires all firearm dealers to obtain a state license, but does not mandate that individuals register their weapons.
Score: 50.5 Grade: B
Delaware has relatively strict gun control measures, including mandatory background checks and purchase restrictions on domestic violence misdemeanants.
#9. Rhode Island
Score: 58.5 Grade: B+
Rhode Island may have comprehensive gun control measures overall, but it stilldoes not prohibit the transfer or possession of assault weapons.
Score: 60 Grade: B+
In addition to requiring background checks, Illinois has instituted some design safety standards for handguns.
Score: 73.5 Grade: B+
In 2014, Hawaii had the lowest number of firearm-related deaths per 100K people. Gun regulation advocates have attributed this to its tight gun control measures.
#6. New York
Score: 81 Grade: A-
New York enacted major gun control reforms in 2013, including an expansion of the assault weapons ban and requirements for ammunition dealers to conduct background checks.
Score: 81.5 Grade: A-
Following the New York reforms, Massachusetts passed a comprehensive gun control bill in 2014 that increased firearm regulations.
Score: 82 Grade: A-
Among Maryland's firearm regulations are a ban on the transfer of certain assault weapons and a mandatory seven-day waiting period prior to the physical transfer of a firearm.
#3. New Jersey
Score: 86 Grade: A-
Republican Gov. Chris Christie may have shifted to the right on the issue of gun control, but his state still has some of the tightest firearm regulations in the country.
Score: 86.5 Grade: A-
Connecticut's extensive gun control laws require firearms dealers to obtain a license and mandate background checks for all firearm sales at gun shows.
Score: 93.5 Grade: A-
California takes the top spot as the state with the strictest gun control measures. Among the regulations in place are required background checks and limitations on the number of handguns an individual can purchase each month.