Last month, a Pennsylvania state lawmaker seeking to reduce road rage shootings introduced a bill that would ban loaded guns in vehicles across the state. Under the legislation, drivers found with a loaded firearm would be charged with a misdemeanor. Law enforcement, military personnel, and game hunters would be exempt.

The bill’s author, Democratic Representative Carolyn Comitta, named her measure “Bianca’s Law” in honor of 18-year-old Bianca Roberson, who was gunned down during a road rage incident in West Goshen, a small town an hour west of Philadelphia, in June 2017. One week before starting her freshman year at Jacksonville University in Florida, Roberson had been driving home from a shopping trip. When she tried to merge onto a southbound lane from the shoulder, she was blocked by a red pickup truck competing to get into the same lane. “Every time she sped up, the pickup would speed up,” another motorist later testified. In the end, Roberson’s 2012 Chevy Malibu veered into a ditch. The teen had been shot in the head by the driver of the red pickup. She died instantly.

The pickup’s driver, 28-year-old David Desper, had a history of drag racing and regularly kept a .40-caliber handgun in his truck’s center console. He was apprehended in Delaware after a four-day manhunt. In September, he pleaded guilty to third-degree murder and related weapons charges and faces 40 years in prison.

“We cannot allow residents of the Commonwealth to live in danger of firearm violence as a result of road rage,” Comitta said upon announcing the bill last month.

Tempers have exploded behind the wheel ever since the advent of traffic. What’s changed is the proliferation of firearms. “There are more guns out there than ever before,” Michael Chitwood, a police superintendent in Upper Darby, Pennsylvania, told the Philadelphia Inquirer after Desper’s arrest. “And you never know who’s armed with a gun when you confront somebody.”

According to an analysis last year by Trace contributor Aviva Shen, armed road rage incidents in America more than doubled between January 2014 and March 2017. In that time, 354 people were wounded and 136 people were killed.

Since then, according to Gun Violence Archive, at least 104 people have been killed and 285 have been injured in road rage incidents involving guns across the United States. The most recent fatal incident occurred on October 5, when Caleb Smith, 24, was fatally shot by another driver while trying to change lanes in Opa Locka, Florida. The alleged shooter was arrested at the scene and charged with second-degree murder.