Appendix: Case Summaries

Cases are grouped by primary event characteristic. Individual cases may have features associated with several characteristics. Cases 1, 8, 13, and 17 are also reported in Table 2 in the main text.

Workplace Targeted

Case 1

A car dealership manager contacted police after a 30-year-old male employee threatened to shoot his supervisor and other employees if he was fired. He told the person to whom he declared his intentions that he would warn him first so that he could escape. Shortly after the mass shooting in Las Vegas, Nevada, he had reportedly commented, “If I were him, I would shoot up a mosque and then shoot it out with the cops.” The dealership was planning to suspend the subject the morning after they contacted the police. California Department of Justice records indicated that the man's wife owned 2 handguns, a shotgun, and a rifle. A GVRO was obtained the following day, 5 firearms were recovered, and a 1-year order after hearing was subsequently issued.

Case 2

A member of the public reported to the California Department of Justice that a 21-year-old man whose employment was recently terminated had threatened to shoot coworkers. Investigation revealed the recent purchase of a shotgun, with the 10-day waiting period expiring in 2 days. Agents served a GVRO the following day and notified the retailer to confirm that the firearm would not be released. Four hundred rounds of shotgun ammunition were recovered during a search of the subject's home. The subject contested the order and denied making threats, but a 1-year order after hearing was subsequently issued.

Case 3

A car dealership hired armed security and reported to police that a 65-year-old male employee had returned to the dealership a day after being fired stating that he could “take somebody out.” During the week before he lost his job, the man told a coworker he would come to work armed to frighten the manager and came wearing an empty handgun holster; the handgun was in his vehicle, which was parked in the dealership's lot. The subject, a veteran, told investigating officers that he had extensive experience with firearms, owned many but had none at home, and was familiar with explosives. When officers asked if there was reason to be concerned about him hurting his former coworkers, he responded, “If we were back on the border of Syria and Israel then hell [yeah].” California Department of Justice records identified him as the owner of 1 handgun. Officers obtained a GVRO the following day, and the court subsequently issued a 1-year order after hearing.

Case 4

A 33-year-old man quit his job with an armed security service after a dispute with a supervisor. Over the next 11 days, he threatened to shoot a specific former coworker and texted others to say that he was watching them and could kill them if he wanted to. The threatened coworker and the company reported the man's behavior to the local police 4 times. California Department of Justice records indicated that the subject owned 4 handguns, a GVRO was obtained, and a 1-year order after hearing was subsequently issued.

Case 5

During telephone calls with his mother and a family friend, a 24-year-old man with a history of excessive alcohol and marijuana use threatened to kill employees of the family business, his family, and himself the following day by shooting or bombing. He had threatened employees twice previously, and a prior conviction for a separate weapons offense had led to residential mental health treatment. The subject's uncle closed the business because of safety concerns, reopened the next workday with private security on site, and reported the incident to the police 3 days later. The subject's mother petitioned for a GVRO 3 days after the uncle contacted the police, and the order was issued. The subject filed an agreement with the order and surrendered 26 firearms (1 shotgun, 4 rifles, 2 assault-type rifles, 18 semiautomatic pistols, and 1 of unspecified type). A 1-year order after hearing was subsequently issued.

Case 6

A 48-year-old male police officer attempted suicide by shooting himself in the head at police headquarters. He survived but later resigned, blaming workplace mistreatment for his suicide attempt. The man's firearms were recovered during a search of his residence, but he retained access to 2 shotguns belonging to a household member. About 8 months after his suicide attempt, he accused members of the police department of continued harassment and stalking. The police headquarters lobby was kept locked with armed officers on duty. A week later, the subject returned to headquarters with the shotguns, claiming that they had been tampered with. Because the household member was unwilling to deny the subject access to the shotguns, the police department obtained an emergency GVRO, recovering the shotguns (along with replica handguns). One-year orders after hearing were issued for the ensuing 2 years.

Case 7

A 37-year-old man celebrated his birthday by target shooting with a coworker, after which they and a friend used alcohol, marijuana, and cocaine. During the celebration, the subject told his companions that he would bring his firearms to the local gas station where he worked and kill infidels and nonbelievers. The coworker contacted police, who obtained an emergency GVRO, contacted the subject 2 days later, and recovered 3 firearms (a pistol and AR-type rifle from the subject's home and a shotgun from his cousin's home). The AR-type rifle did not have a serial number and had prohibited design elements, so the subject was arrested for possession of an assault weapon. A temporary order was petitioned for and granted after the emergency order expired. A 1-year order after hearing was subsequently issued.

School or Children Targeted

Case 8

A 21-year-old male posted a series of threatening statements on Instagram that were directed at his former high school, including, “Rip [name deleted] high school,” “Nobody w[ill] be graduating from [ZIP code deleted],” “I hate all of u,” “Hope I die tonight somehow,” and “Dead or in jail.” An acquaintance who saw the posts flagged down a police officer, and a different acquaintance reported a post that appeared to show the man holding an AR-type rifle. Both reporting parties were aware of prior school shootings and were concerned about a recurrence. The school district learned of the threats the following day and closed the school, and the subject was arrested that afternoon on a charge of making a threat with intent to terrorize. A temporary GVRO was obtained, and a 1-year order after hearing was subsequently issued.

Case 9

A high school assistant principal contacted a juvenile services police officer after a 15-year-old male student spoke favorably of the Parkland shooting, stating that “school shooters are gods,” and threatened a mass shooting and bombing at a school assembly scheduled to take place in 2 days. The subject had also threatened the student who reported this information and was suspended from school for 5 days. The subject had a prior history of violent threats, racist behavior, and telling other students that he could get access to firearms. Police arrested the subject at his home on a charge of criminal threat and obtained a GVRO. The case was subsequently dismissed at the request of the petitioning agency.

Case 10

A school administrator reported to the police that a 14-year-old male student with a history of racist comments at school had posted videos on Instagram of himself using firearms, favorable comments about school violence and shootings, racist comments, and suggestions of animal cruelty. A related investigation had determined that the student used school computers to research firearms and search on terms such as “white power.” His father owned a 9-mm semiautomatic pistol and a .30-caliber rifle. The student was taken into custody for an emergency psychiatric evaluation and claimed that he had been joking. A GVRO was obtained, and the father's firearms were turned in to a licensed retailer the day the order was served. A 1-year order after hearing was subsequently issued.

Case 11

Five children aged 11 to 15 years contacted police after a 62-year-old woman told them she was going to “blow their heads off” while pointing what appeared to be a firearm at them. The investigating officer interviewed the subject at her home shortly after interviewing the children. The subject confirmed her behavior but reported that the object was a paper towel roll wrapped in black duct tape. She added that a real revolver was under a table in her living room and gave the officer permission to search for it. The officer obtained an emergency GVRO while at the subject's home, took custody of the firearm, and arrested the subject on a charge of criminal threat. The subject continued to state that she would like to “teach those kids a lesson” and “go to their homes to finish off each one of them.” A 1-year order after hearing was subsequently issued.

Case 12

When the principal and a security officer at an elementary school approached a 26-year-old man after he drove over a planter into the school's parking lot, the man threatened to punch someone. After being asked to leave, he stated he was going to explore the school grounds, drew a knife, and threatened to stab the principal and officer. More officers arrived and took the subject into custody after a struggle. Investigation revealed that the subject was scheduled for jury duty 2 days after the incident, had posted images of ammunition and vague threats to his family on Facebook, and owned a Glock semiautomatic pistol. The police obtained a temporary GVRO while the subject was still in custody, citing concern that he might return to the school to seek revenge for his arrest, and recovered 1 firearm from him. A 1-year order after hearing was subsequently obtained.

Medical or Mental Health Condition

Case 13

Employees at a Veterans Service Center that supplies social and behavioral health services contacted the police early on a Friday evening, immediately after a 48-year-old client threatened them while on speakerphone, “I'm going to come and hunt you down and take you out! Don't think I'm a little worm, I can take you all out, I know where you all are!” The client was a Gulf War veteran diagnosed with posttraumatic stress disorder. On the basis of their prior contacts with the subject, the employees believed the threats were credible. After interviewing the employees, the investigating officer went to the subject's home, arrested him on a charge of criminal threat, and presented a petition to a judge by telephone on Saturday. A GVRO was issued. At the hearing for a 1-year order after hearing, the subject denied possessing firearms. The order was issued.

Case 14

Just after 1:00 a.m., a 47-year-old man deliberately drove his SUV onto a sidewalk and accelerated toward pedestrians, shouting “I'm going to kill you!” The man fled the scene without hitting anyone but was taken into custody and arrested a few minutes later on a charge of assault with a deadly weapon. A month earlier, the man's father had contacted the police concerned that his son was acting delusional and paranoid and was claiming he might die that day. The father reported that his son owned 4 handguns, 3 AR-type rifles, and a shotgun. California Department of Justice records, which do not include rifles and shotguns acquired before 2014, indicated that the man owned 10 handguns. The subject had prior contact with law enforcement related to controlled substance use, delusions, and violent threats and reported having several firearms in a safe in his apartment. A GVRO was obtained the day after his arrest, 8 firearms were recovered, and a 1-year order after hearing was subsequently issued.

Case 15

An orthopedic clinic contacted the county sheriff immediately after a 44-year-old male patient, upset about his treatment, left the clinic threatening to retrieve his shotgun from his home and shoot everybody in the clinic. Deputies went to the patient's home, where his vehicle was present but his mother declined to provide information. Four days later, the patient contacted his health insurer threatening to shoot insurance company employees and clinic staff and stating, according to the deputies' report, that “the next time he was going to be seen was on CNN” and that “if they were going to mess with his health, he would mess with theirs.” The following morning, deputies returned to the patient's home, where his mother again declined to assist. They contacted the patient, who was inside the house, by telephone; he reported possessing a rifle and a shotgun. California Department of Justice records confirmed he owned 2 semiautomatic pistols. Deputies obtained an emergency GVRO, persuaded the patient to come out of the house, and informed him of the order. After obtaining a warrant, they searched the house and vehicles belonging to the patient and his mother, recovering shotgun and rifle ammunition but no firearms. The patient was arrested on a charge of criminal threat, and a criminal protective order was issued 2 days later. Bail was set at $100 000, and the patient remained in custody during the adjudication of his case. About 4 months later, he pleaded no contest to a felony charge of criminal intent to terrorize and was ordered to show proof of relinquishment of his firearms. The patient reported that his 2 handguns had been stolen and that he had given his rifle and shotgun to friends.

Case 16

Law enforcement officers responded to a call from a trailer park about a 58-year-old intoxicated man who was threatening to kill people because he had cancer and could not be “fixed.” The man threatened to kill any law enforcement officers who approached his trailer and to kill others if officers left the scene. After several hours of negotiation, during which the subject told the agency dispatcher that he had loaded his firearms, he was persuaded to leave his trailer. Officers had obtained a temporary GVRO; they arrested the man, took him to jail after emergency department evaluation, and recovered a shotgun and 2 handguns from his trailer. The subject was released on bail 2 days later with a prohibition from firearm or ammunition possession during adjudication of his case.

Political, Social, or Domestic Motivation

Case 17

An acquaintance of a 31-year-old man who was known in his Muslim community as a supporter of the Islamic State contacted police to report that the man made repeated threats of mass violence. The acquaintance was concerned about a mass shooting at a nearby mosque or shopping mall. Investigation revealed that the man was on the Terrorist Screening Center Watchlist. He was not known to own firearms but had recently purchased an FN 5.7 semiautomatic pistol, a powerful handgun originally available only to military personnel and law enforcement officers. Because of California's 10-day waiting period, the subject had not yet acquired his handgun. The police contacted the California Department of Justice, which obtained a GVRO the following day, preventing acquisition of the firearm. No information on an order after a hearing was available.

Case 18

The Federal Bureau of Investigation (FBI) contacted a local police department about a 22-year-old man who was the close associate of a man recently charged with providing material support to the al-Nusra Front, a foreign terrorist organization. Both men had traveled to Turkey on one-way tickets, possibly to cross into Syria, but had returned to the United States. According to the FBI, the al-Nusra Front encouraged its members to engage in lone-wolf attacks on large public gatherings rather than joining the conflict in Syria. One week before the FBI contact, the 22-year-old man, who was not previously known to own firearms, purchased an AK-47–type rifle, meaning that the 10-day waiting period would expire in 3 days. The man had begun working at an indoor firing range 1 month earlier but was fired the day before the FBI contacted the police. According to the FBI's interview with the range manager, the man disliked dealing with customers but was very interested in handling firearms. He lived within walking distance of public events, scheduled 2 and 3 weeks later, that were expected to draw 50 000 to 100 000 people. The police department obtained and served a GVRO the following day, blocking acquisition of the rifle. A 1-year order after hearing was subsequently issued.

Case 19

A woman contacted the police to report that the previous evening her intimate partner, a 32-year-old man who lived with her and her 22-month-old son, had stated that he slapped the child while she was at work, leaving red marks on the child's face. The woman left with the child and presented to the police station the following morning for an interview. She reported more than 10 prior similar events. That morning, she received text messages from the subject, including, “I promise you. If something, or anything happens to me or my things, I will be karma. And I will come back 10 fold on anybody and everybody,” and “I don't want to shoot or kill anybody. But I'm promising you if something does happen. And if I pull the trigger on one person. I'm not stopping there until I'm caught.” The woman was aware that the subject owned an AR-type rifle, an AK-type rifle, a .22-caliber rifle, and 2 semiautomatic pistols. Police obtained an emergency GVRO that day, arrested the man, and recovered 1 handgun. A temporary order was issued 5 days later. According to the petition, the subject still had access to firearms. A judge dismissed the matter 3 weeks later at a hearing that the petitioning law enforcement agency did not attend.

Case 20

A 21-year-old man pointed a gun at another person stating that he could kill him any day of the week, that it was very easy to kill people, and that he would not mind killing others. He told the threatened person that he had killed 4 people who were terrorists. Law enforcement obtained an emergency GVRO. No further information is available.

Case 21

A 47-year-old woman was the mother of a young man shot and killed by police officers. At a public hearing of that department's police commission 10 weeks later, she stated repeatedly that because police officers had killed her son, she intended to kill police officers. Twelve days after the hearing, a search of California Department of Justice records identified the subject as the owner of 4 handguns. Two weeks after that, a temporary GVRO was issued. The subject denied possessing any firearms. A petition for an order after hearing was denied.