For years, Brown had gone on unhinged rants in his classroom. His wife left him when he wouldn't get psychiatric help and eventually he was suspended from his teaching position.

.30-caliber M1 carbine rifle, .25-caliber automatic pistol, .38-caliber revolver

.223-caliber Ruger Mini-14 semi-automatic rifle with collapsible stock, silencer; .22-caliber pistol with silencer; Pistol

9mm Smith & Wesson Model 459 automatic pistol

9mm Israeli Military Industries Uzi Model A carbine; 12-gauge Winchester 1200 pump-action shotgun; 9mm Browning P-35 Hi-Power pistol; .45-caliber Colt pistol; 12-gauge Smith & Wesson shotgun

Uncertain. Had a 30-06 rifle but had previously been found with other guns. - https://en.wikipedia.org/wiki/Michael_Silka

.223-caliber Ruger Mini-14 semi-automatic rifle; .357-caliber Ruger Blackhawk revolver; 20-gauge Winchester pump-action shotgun

Sentinel revolver; .357-caliber Magnum Smith & Wesson revolver; 9mm Browning semi-automatic pistol; 12-gauge Benelli Riot semi-automatic shotgun; Smith & Wesson pistol; .22-250 rifle with scope; Pump-action shotgun; Semiautomatic pistol

Brought, Not Used

Brought, Not Used

Sig-Sauer used for suicide, other pistols not used. .380-caliber Intratec MAC-11 semi-automatic machine pistol, .38-caliber snub-nose revolver, 9mm Sig-Sauer pistol, 7.62mm AK-47 semi-automatic rifle

Taurus .38-caliber revolver; Jennings J-22 .22-caliber semi-automatic pistol

admitted himself into a PTSD treatment program

.22-caliber Ruger sawed-off semi-automatic carbine rifle

.22-caliber rifle with stock sawed-off and pistol grip; 12-gauge Maverick pump-action shotgun

Suicidality, Mood disorder, Thought Disorder

9mm Llama semi-automatic pistol; .32-caliber revolver; 12-gauge shotgun

12-gauge pump-action shotgun; 12-gauge shotgun; .22-caliber rifle

Brought, Not Used

Had been diagnosed with mild autism, generalized anxiety disorder and paranoid personality disorder.

.45-caliber semi-automatic pistol; Ingram MAC-11 machine pistol; 9mm Intratec TEC-9 automatic pistol; .223-caliber Colt AR-15 rifle; 9mm Ruger P85 pistol

Brought, Not Used

Brought, Not Used

Beck had been in and out of psychiatric hospitals and had attempted suicide several times in the past.

Mitchell Scott Johnson; Andrew Douglas Golden

.380-caliber FIE pistol
.30-06 Remington 742 rifle with scope
.38-caliber Charter Arms revolver
.38-caliber Smith & Wesson revolver
.380-caliber Star pistol
.30-caliber Universal M1 carbine replica rifle
.357-caliber Ruger Security Six revolver
.22-caliber Double Deuce Buddie two-shot derringer
.44 Magnum Ruger rifle
.38-caliber Davis Industries two-shot derringer

Brought, Not Used

High-capacity magazines (capacity unstated)

Eric Harris and Dylan Klebold were radically different individuals, with vastly different motives and opposite mental conditions.

Colt 1911A1 (.45)
Glock 17 (9mm)
H&R Revolver (.22)
Raven MP-25 (.25)capacity unstated; After Barton's suicide, investigators found in his minivan a duffel bag stuffed with 200 rounds of ammunition and the two handguns used in the shootings -- a 9mm Glock that Barton had purchased in November 1993 and was legally registered to him, and a Colt .45-caliber handgun that was not, according to the Bureau of Alcohol, Tobacco and Firearms.

His mental health continued to deteriorate and he began to suffer from severe depression and paranoid delusions.

.380-caliber AMT semi-automatic pistol
9mm Ruger P85 semi-automatic pistolThree 15-round magazines

Thought disders. Had a history of paranoia and mental instability

Three 15-round magazines. 9mm Glock 17 pistol

In 1993, he was ordered to undergo psychiatric evaluation and anger management courses after he kicked in and damaged an elevator door for which he was arrested. The psychiatrist who examined him at the time of this arrest found that Uyesugi suffered from a delusional disorder and paranoia, but found him not to be dangerous. He felt like he was being poked by someone, sometimes all day long, for years before the shooting. He was paranoid and believed that his coworkers had killed his pet fish and were sabotaging his work. He was afraid he would lose his job if he couldn't master a new training. He saw dark shadows when trying to sleep. He heard voices and threatened his coworkers.

Mossberg 500 Cruiser 12-gauge 8-shot pump-action shotgun[1]

60-round, large-capacity feeding device

Brought, Not Used

McDermott was undergoing psychiatric treatment and taking medication.

.30-30 Marlin rifle with scope; 7.62mm SKS 1954R rifle; .38-caliber special revolver; Remington H70 shotgun. None has 10+ capacity.

Brought, Not Used

He had been in and out of psychiatric hospitals for schizophrenia for 20 years. He had a recurring delusion that he was Michael the Archangel and he was on a mission to rid the world of wicked people. He was witnessed doing other bizarre things indicative of psychosis shortly before the shooting.

A man accused of murdering four people at a day-labor office earlier this week has mental problems and was once committed for treatment.

Shotgun only weapon used - 12-gauge shotgun
.223-caliber Ruger Mini-14 rifle
.22-caliber Magnum derringer
.45-caliber Ruger pistol
.22-caliber rifle with scope

Brought, Not Used

Brought, Not Used

Williams's cousin described him as being depressed.

He had no prior criminal record nor mentalhealth problems.

capacity unstated; Ohio nightclub shooter had 35 rounds when he was killed. 9mm Beretta pistol, all of which are standard at 15 rounds aside from special "resztricted" models

Meds unspecified. While in the USMC, he was given medications for his mental problems. Writings found in Gale's possession indicate that he may have suffered from schizophrenia.

Police have said Ratzmann had no diagnosed mental health problems, but several congregants reported that he seemed depressed in recent weeks.

American Indian

He was under treatment for depression, and had been prescribed Prozac as an anti-depressant.

A spokesman for the Santa Barbara County Sheriff's Office speculated that San Marco's paranoia and history of mental illness may have motivated her to commit the murders.

Rugar P94 (10 round) and pump shotgun, several bandoliers (over 300 rounds) worth of ammunition for the guns

Brought, Not Used

Mood and thought disorders, Police were unable to find any record that he had been treated for mental illness or was on psychiatric medication.

12-gauge Browning shotgun
9mm XD Springfield Arms semi-automatic pistol (16 round capacity)
.30-06 Ruger bolt-action rifle. ; with a 9 mm handgun, 12 gauge shotgun, .30-06 bolt-action rifle, about 600 rounds of ammunition, cans of black powder, a stun gun, two knives, a change of clothes, an apparent truss board and a box containing a hammer, hacksaw, pliers, wire, screws, bolts and tape

Brought, Not Used

all those years of undealt-with depression resulted in a psychotic break; Mr. Roberts had no criminal record or history of psychiatric illness.

Mossberg Maverick Arms M88 shotgun with a pistol grip, .38 Special Smith & Wesson M36 revolver

Available information indicates that Talovic was socially isolated and may have suffered from mental health issues, that he was using marijuana and possibly other drugs in the months prior to the attack.

Cho had previously been diagnosed with a severe anxiety disorder. He continued receiving mental health therapy as well until his junior year, when Cho rejected further therapy.

Peterson left and got a police-style AR-15 rifle from his truck, forced his way back into the apartment and fired about 30 rounds at about 2:45 a.m.

No psychological screening was performed in his hiring.

Two 30-round magazines taped together

He was attending therapy sessions, taking medication and being hospitalized for depression by the time he was 6 years old. Throughout most of his life, he and his family were plagued by his psychiatric problems. The day after he turned 14, he was sent to a mental health treatment center for threatening to kill his stepmother Candace Hawkins with an axe. Four months later, he became a ward of the State of Nebraska, which lasted nearly four years. He had undergone two psychiatric hospitalizations, and was diagnosed with attention deficit disorder, an unspecified mood disorder, oppositional defiant disorder, and parent-child relationship problems. His extensive treatments cost the state USD$265,000.

One revolver and one .40 S&W (16 rounds)

Suicidality, and he was known for histrionics and disruptions at city council meetings. His mounting debt was a stressor.

1st two used: 9mm Glock 19 pistol, 12-gauge Remington Sportsman 48 sawed-off shotgun, 9mm short Kurz SIG Sauer P232 pistol, .380-caliber Hi-Point CF380 pistol

Hi-Point Model JHP .45-caliber, 9-round

Suicidality, He called his girlfriend two hours before the shooting to say he was going to kill his boss.

He was diagnosed with paranoid schizophrenia 10 years before the shootings.

Brought, Not Used

Stewart's defense team argued that Stewart suffered from mental illness including depression and borderline personality disorder, and that he had been taking regular doses of the prescription sleep aid Ambien far in excess of the recommended limit. Combined with prescriptions for an antidepressant and anti-anxiety drug, they argued, it made Stewart essentially a lethal sleepwalker.

30-round magazine; Allegedly fired 98 rounds during the attack. At least one magazine with a
30 round capacity was recovered at the scene.

Mr. Wong displayed no outward sign of mental illness. But it now appears that he was harboring a growing paranoia, with a fixation on law enforcement rooted in a few brief encounters that seemed to convince Mr. Wong that the police were out to do him in. Just before setting off on his massacre, he sent a two-page delusional rant to a Syracuse television station saying the police were spying on him, sneaking into his home and trying to get into car accidents with him. Nga said that she did not recognize the letter’s handwriting as being her brother’s, and that he had not told the familyabout his paranoia about the police. The letter might be a sign that he had “lost his rational thinking,” she said. People who knew Wong said he exhibited no outward signs of mental instability, although a letter he wrote that was delivered to a newspaper after the shooting indicated he was paranoid and suffering from mental illness.

Middle Eastern

30- and 20-round magazines; Hasan fired at least 220 rounds of ammunition and has 200 rounds in his
pocket when he was detained.

Psychiatrist Dr. Steven Dinwiddie said among solo mass murderers, mental illness usually attracts and twists religious beliefs -- not the other way around.

About six months before the shooting, he became delusional, assaulted police officers, and sexually assaulted his stepdaughter. He believed that he was Jesus Christ, that he had been cursed, that his wife could get $37 billion from an online church, and that he could fly and would save the world. . During a court-ordered mental health evaluation, Clemmons told psychologists he had experienced hallucinations in May 2009 of "people drinking blood and people eating babies, and lawless on the streets, like people were cannibals". He claimed the visions had since passed. He also claimed to have no faith in the American justice system and thought he was being "maliciously persecuted because I'm black and they believe the police". The evaluation, completed by two psychologists from the Western State Hospital on October 19, concluded Clemmons was dangerous and presented an increased risk of future criminal acts. After a mental evaluation, a psychologist concluded Clemmons was competent to stand trial on the charges, which eliminated him as a candidate for involuntary commitment. An attorney for Clemmons notified the court he planned to pursue an insanity or diminished-capacity defense.

17- and 15-round magazines, though unsure about the smaller handgun

The FBI said that Loughner had a second thirty-round magazine, and two standard mags (15 rounds apiece).

Interviews with Loughner's parents revealed they were deeply concerned about their son's increasingly angry and erratic behavior. His mother, Amy Loughner, said he no longer used alcohol and had tested negative for drugs. The papers also reveal Loughner did not seek mental health treatment. When he was expelled from college, his parents were urged to have him evaluated, but they never followed up. Loughner was rejected from enlisting in the Army in 2008 because he admitted he had used drugs. Loughner had a history of mental illness and drug use. He was rejected from Army enlistment in 2008 after failing a drug test and admitting to drug use on his U.S. Army medical history application form, which should have prohibited Loughner from buying a gun for at least one year.

20- and 30-round magazines; Police recovered 450 rounds of AK-47 ammunition from Sencion’s van and “box upon box” of additional ammunition at his home.

South Lake Tahoe police said the department took Sencion into protective custody during a mental health commitment in April 2000 and that he fought with officers. He was not charged. Sencion was taken into protective custody during a mental health commitment in April 2000 but no court order was involved and it remains unclear if a record of the incident was reported to the NICS database.

.44 Magnum Smith & Wesson revolver, .45-caliber Heckler & Koch pistol, 9mm Springfield pistol, extra magazines and ammunition; 75 rounds fired

The Associated Press reports that the incident left the ex-Marine with post-traumatic-stress disorder. His ex-wife, who was a stylist at the salon, had claimed that her husband was unstable and physically abusive during their marriage and prior to the accident, according to the AP. Her friend Sharyn White told the AP that Michelle Fournier Dekraai said that her ex-husband had stopped by the salon weeks prior and threatened to kill her and the others at the salon. Though White said her friend told her that everyone else at the salon laughed off the threat, she took it seriously. Dekraai had been diagnosed with Post Traumatic Stress Disorder, and during a custody suit his ex-wife had filed court papers claiming that he was mentally unstable and had threatened to kill himself or someone else at least once.

.45-caliber Hi-Point ACP pistol, .357 Magnum six-shot revolver

One family friend called Paek an aggressive and violent personality. Song described her brother’s mental health as deteriorating in the 2006 paperwork, noting that he was suicidal. Korean media members translated statements by people who knew Paek and said he’d lost his right eye when he was the victim of a shooting in Virginia.

a gunman opened fire with a .45-caliber semi-automatic handgun with four fully loaded 10-round magazines on the university's campus

“He wasn’t showing any signs of violence or anything toward anyone,” the official said. “He didn’t show any mental illness. He seemed like a regular, ordinary guy. He was quiet.”

Thought disorders. Members of the suspect's family tell a newspaper they're not surprised, as he suffered a mentally illness. Stawicki had a history of mental illness.

100-round magazine. 12-gauge pump-action Remington 870 shotgun, .40-caliber Glock pistol
.40-caliber Glock pistol, .223 Smith & Wesson M&P15 AR-15 style rifle

Alleged Aurora, Colo, shooter James Holmes met with not one, but at least three mental health professionals at the University of Colorado prior to the massacre. His name was brought to the attention of the university's Behavior Evaluation and Threat Assessment team or BETA for short. A flow chart released by the university shows guidelines for action that could be followed if a person is deemed a direct threat. While a student at the University of Colorado, Holmes was treated by the school psychiatrist, who expressed concern about his behavior and referred him to the university Behavioral Evaluation and Threat Assessment (BETA) team. They took no further action and he was never adjudicated mentally ill.

Suicidality. "None of that would have been enough to satisfy authorities that Page should be detained for a mental health evaluation for his own safety or the safety of others, Dunn said. But the suicide scare of 1997 would have been enough to alert Army doctors that Page had mental illness and was unfit for duty, said John Liebert, a psychiatrist who does fitness exams for the military and has written an academic text on suicidal mass murderers."

Two 15-round magazines; Engeldinger fired at least 46 bullets during the shooting. At his home,
police recovered packaging for 10,000 rounds of ammunition.

Andrew Engeldinger's parents pushed him for two years to seek treatment for what they suspected was mental illness, but even though he became increasingly paranoid and experienced delusions, there was nothing more they could do. Engeldinger was never formally diagnosed with a mental illness, but his family was concerned enough by their son's behavior, which included claims that he was being followed, to enroll in a free, 12-week "Family to Family" course offered by the Minnesota National Alliance for loved ones of people with mental illness before he cut off contact in late 2010. His family suspected he had paranoid schizophrenia and two years before the shooting they reached out on his behalf to the National Alliance on Mental Illness.

30-round magazines; 5.56mm Bushmaster XM15-E2S AR-15 style semi-automatic rifle, 10mm Glock 20 pistol, 9mm SIG Sauer P226 pistol, .22-caliber Savage Mark II bolt-action rifle, 12-gauge Izhmash Saiga semi-automatic shotgun

Brought, Not Used

Adam Peter Lanza had Asperger's Syndrome, a disorder on the autism spectrum that makes social interaction difficult. Adam struggled with a sensory disorder from a young age. As Adam got older, he "was not open to therapy" and "did not want to talk about problems and didn’t even admit he had Asperger’s". However, the doctors who saw him didn't think he had a propensity for violence. Lanza’s mental health was also scrutinized after the shooting, and while his social isolation had been noted, we did not find evidence that concerns had been brought to the attention of a public authority.

Barretta M9 has 15 round capacity; a Remington 870 Express shotgun 6+1

Aaron Alexis was treated for insomnia but never sought help for mental illness. According to VA records, he never sought an appointment from a mental health specialist, and had previously either canceled or failed to show up for primary care appointments and claims evaluations examinations he had scheduled at VA medical centers. He had also received treatment for mental health conditions at two VA hospitals beginning in August, 2013 following an incident where he called Newport Rhode Island Police to report hearing voices.

.40-caliber Taurus pistol, Mossberg 500 shotgun with pistol grip