Table 3 Typology of incidents, with representative examples

1. The victim uses someone else’s gun—almost always the perpetrator’s gun. 2% of incidents

 • Two teenagers, known to the residents, demand money. The older teen tries to shoot his gun, which jams. His gun is wrestled away and one of the residents shoots him 3 times with it, killing him. The younger perpetrator is held at gunpoint for the police

 • A teen tries to rob a stand selling holiday items. When he puts his gun down to pick up the cash that the employees put on the counter, one grabs the perpetrator’s gun and shoots him in the face

2. Defender is a security guard or off-duty police officer. 6% of incidents

 • At 2 AM outside an apartment complex, a woman has been robbed by 3 men. A security guard follows them and gunfire is exchanged. The guard holds all 3 men for the police

 • Early in the morning, 2 armed masked suspects enter an all-night restaurant to rob it. Seeing a security guard, they shoot and wound him. He fires back but they flee

3. Drug-related. 4% of incidents

 • The victim is shot when he does not pay for the illegal marijuana he is purchasing. He fires back but hits no one and is charged with illegal gun possession

 • In a parking lot, two young men display handguns to rob a young man during a drug deal. The dealer grabs his own gun and shoots both men, killing one. The two perpetrators had committed another armed robbery that day

4. Gang-like combat. 6% of incidents. The combatants seem to know each other, and shoot-outs typically occur

 • In the afternoon, in what news reports call a drive-by shooting, four men in a car shoot and wound one young man standing with a group of men. The others in the group fire back and the car drives away

 • In the early morning at a gas station, 3 young men are in an expensive car. Another car pulls up with 3 young men in it and they try to rob the first group. Someone in the expensive car shoots one of the perpetrators, and both cars speed away

5. Romantic partner disputes. 11% of incidents

 • Two men shoot each other over a woman. The victim is shot in the face, the perpetrator is shot in the leg

 • A man arrives at the home of his former wife. He hits her male friend with a baseball bat. The male victim shoots and kills the ex-husband

6. Other family issues. 6% of incidents

 • In the afternoon, a young man pushes his way into the home of his grandparents. An altercation occurs over money, and the grandfather shoots and kills the grandson. The grandfather is arrested

 • Early in the morning, a young man is choking his mother and is shot and killed by his 60-year-old father. The father is arrested

7. Escalating arguments. 13% of incidents

 • A fight between neighbors over loud music ends with one of them dead. In an apartment complex, a couple upstairs yells at a couple in a car to keep their music down. Later that day, when the car owner discovers that his car has been vandalized, he races upstairs to confront the person who had yelled at him. He opens the apartment door and is shot dead

 • Saturday near midnight, two men are arguing with each other outside a residence. One pulls a gun, both men fire at each other, and one is wounded

8. Store robberies. 9% of incidents

 • In the late afternoon, at a fast-food restaurant, an armed robber fires warning shots and demands money. A nearby store owner hears the shots, goes to the scene, and confronts the robber as he is leaving. A shootout occurs, no one is wounded, and the robber gets away with the money

 • A young armed male tries to rob a store and is shot three times by an employee. The wounded perpetrator is arrested at the store

9. Street robberies. 5% of incidents

 • In the early morning, a young man shoots into a group of teens he says were chasing him. A wounded teen is subsequently brought to a hospital by friends who say he was shot in a drive-by

 • Shortly after 10 PM, a 27-year-old male says that a young man tried to rob him and he shot the robber many times and killed him, but not before the robber shot and wounded him. Residents called 911. The perpetrator may have also robbed another person that night

10. Unoccupied vehicle theft. 5% of incidents

 • Around 3 AM, a man at home awakens and sees people entering vehicles in his driveway. He goes outside and shoots at them. They shoot back, no one is injured, and they leave

 • A man hears a commotion outside his home and sees two men and his truck hood open. He fires a warning shot into the grass and they flee

11. Unarmed burglary. Described as a burglary in the news articles or the perpetrator charged as committing a burglary rather than a robbery or home invasion. 7% of incidents

 • A man’s home has been burglarized in the past. In the early morning, his dog is barking wildly. He finds a burglar in his garage. His surveillance camera shows him firing warning shots, and the burglar runs away

 • At 3 AM an unarmed burglar breaks into a business building by coming through the roof. He is shot and captured by the owner who happens to be living there

12. Home invasions. 20% of incidents. A little over half the time the perpetrator breaks in or the victim finds an armed perpetrator inside the home

 • At 2 AM a 37-year-old starts banging on the back door. An 86-year-old resident grabs his shotgun, fires a warning shot, and then wounds the perpetrator in the torso when he continues to try to get in

 • A little before sunset, an 18-year-old kicks the door down. The homeowner shoots him and calls the police. The teen flees, goes to the hospital and dies

 • Around 2 AM, an armed 27-year-old tries to enter a home and is shot and killed by the resident (no other information available)

 • A male in his late 60s shoots and kills a man in his early 40s he saw on his outside balcony

 • Shortly before sunrise, the next-door neighbor in his 40s, armed with a machete, breaks windows to get into the home and is shot and killed

 • Around 11 PM, two men knock on the door and enter an apartment with guns drawn in an attempt to rob the occupants. A woman resident kills one of them and the other flees

13. Miscellaneous. 6% of incidents

 • A 30-year-old male tries to cash a fraudulent check. Police arrive at the bank, but the man has left. Police see him and chase him. Running away, he jumps into the backyard of a homeowner who has a firearm. The homeowner shoots at him but misses. He eventually is caught by police after a long chase

 • In the morning, a teen pushing a lawnmower asks a man in his 70s if he can borrow his cell phone. The teen pretends to make a call and then runs away with the phone. A neighbor with a gun gets into his vehicle, finds the teen and gets the phone back. The teen runs away

 • A man in his late 60s goes to the police with this story. He picked up an unknown woman and rejects her prostitution offer. They get out of the car and she tries to take his wallet, an altercation occurs, and people come to the aid of the woman. The man draws his gun for protection, then puts it in his back pocket, whereupon a male with an umbrella who had come to the aid of the woman steals the gun

 • A road rage incident ends with the two drivers stopping, getting out of their cars and arguing in front of an unrelated person’s residence. The resident comes out with a gun and tells them to leave. They do so, but the resident says one motorist tried to run him over, so he shoots at the vehicle multiple times, wounding the driver