Drivers with guns in the car more likely to drive aggressively. Also more likely to have a violent response to road rage.

Courtesy of CNN:  

According to the National Highway Traffic and Safety Administration, 66% of traffic fatalities are caused by aggressive driving. Over one-third (37%) of aggressive driving incidents involve a firearm, according to research for the AAA Foundation for Traffic Safety. Research also indicates that aggressive or risky drivers are more likely than safer drivers to: be young and male, have been diagnosed with borderline personality disorder, have received driving citations (for moving and non-moving violations), score higher on measures of aggression and psychiatric morbidity, use illicit drugs, drive more miles per day, drive in denser traffic more often, abuse alcohol, have higher levels of stress, and be more likely to attribute blame to other drivers. 

They are also more likely to carry firearms in their car. 

Of course, not all gun owners are alike, just as not all drivers are. But if the gun owners who drive with a gun are more likely to drive aggressively than those without a gun in the car (gun owners or not), the risk rises not only that a road rage incident will occur, but that it will become lethal. Many studies have found that where there are more guns, there are more deaths -- not fewer.

I think for many of us this falls into the "no shit Sherlock" category.

However I found this next part a little surprising.  

Ample research also documents that the mere presence of a weapon can intensify aggression. 

One study compared responses to a pickup driver stalled at a light for 12 seconds. When the truck sported a military rifle in the rear window, other drivers honked more quickly and more often at the driver than they did if no firearm was visible. This so-called weapons effect counters the "polite society" argument, showing that weapons provoke visceral responses that increase aggression.

That seems a little counter intuitive. One would think that the presence of a weapon clearly on display might make people a little hesitant to anger the driver. But instead it seems that merely seeing a gun makes even unarmed drivers respond more aggressively.

One of the pieces of advice that I give to young people that I work with that are just starting out as drivers is to always be a polite driver and to not overreact to poor drivers they may come across on the road.

I sometimes add that since this is Alaska it is quite reasonable to assume that the driver of the car that just cut you off in traffic is packing heat and will shoot you during an angry confrontation.

Now I am wondering if that might not have made some of these youngsters even more likely to pull up to them at a stoplight and flip them the bird.