It turns out there's also been a huge spike in cases of road rage all across this country. Road rage has more than doubled in a five-year period. And abc's gio benitez takes a look at an american epidemic. Reporter: Angry gun shots all thauz this man says two young men cut him off, an extreme example of road rage. And just last week, a bruising brawl at a california intersection between a lawyer and a retired police officer. Aggressive drivers are a growing threat on the roads. In fact, the most recent study from the u.S. Department of transportation attributes more than a thousand death it is to road rage -- up 170%. Let's go for a ride, doctor. Reporter: Psychologist dr. Ryan fuller says cars become weapons in the hands of stressed drivers. What's the mind-set of someone who is really angry on the road? Now they perceive someone cutting them off as just one step too far. Reporter: Watch this. Just this weekend, a driver on a los angeles highway, cut off another driver, threw a can at him, and got out of his car and yelled. So what do you do if attacked? Doctor fuller says first keep your cool. Take a deep breath. Slow things down. Reporter: Most importantly, don't make eye contact because that can be interpreted as a challenge. Sometimes we see people get out of the car, start yelling. Is that something they should do? The best thing they should do is stay in their car under any circumstances. Like this man, ignoring the angry marine outside his window. Just keeping his eyes on that road.