What Triggers Mass Shootings?

cadaver over crime scene tape and Hand holding gun
The nation is reeling from two mass shootings in as many days, leading many to wonder, yet again, what could drive people to such acts of mass violence. Are there warning signs -- red flags -- that can signal trouble may be brewing? And if you notice them in someone you know, what should you do about it?

An Army psychiatrist, Maj. Maj. Nidal Malik Hasan, is accused of shooting fellow solders at Texas' Fort Hood Thursday, killing 13 people and wounding 30. And Jason Rodriguez is charged opening fire Friday in the Orlando, Fla. engineering firm that fired him off two years ago, killing one person and wounding five.

Special Section: Tragedy at Fort Hood
Fort Hood: The Victims

Dr. Alan Lipman, a clinical psychologist and director of the Center for the Study of Violence<.link>, in Washington., D.C., says there are three types of people who go over the edge like that: the person is psychotic and has lost touch with reality, the person is depressed and feeling hopeless, or the person is a psychopath and enjoys killing. "It's always going to be one of these three," he told CBS News.

Lipman says people don't always just "snap" -- it's "not always so quick. "First of all," he explains, "there's a period of buildup, then there's more anger and hopelessness, and then, finally, there is the trigger -- something that causes them to go from just an angry person to being a killer. When Major Hasan (a devout Muslin), discovered he was being deployed to the Middle East -- that may have been was his trigger." Rodriguez complained to a reporter that the engineering firm had left him "to rot."

More Coverage of the Tragedy at Fort Hood:

Fort Hood Hero Cop Was Ex-Partner"s "Mighty Mouse"
Hasan Likely "Lone Wolf," Officials Say
Hasan Reportedly Felt U.S. Attacked Islam
List of Fort Hood Dead, Wounded
"Allahu Akbar": Hasan's Words as He Fired?
Hasan's Actions "Despicable," Family Says
Female Cop Hailed as Ft. Hood Hero
U.S. Army Base Violence Has Bloody History
Tragedy at Fort Hood

What are some of the warning signs that someone in your life might snap and be capable of acts of violence?

1) Notice or look for someone who becomes more withdrawn from others -- friends, family, co-workers.

2) They begin to lose interest in their usual activities: They stop exercising, listening to music, going to work -- the things that mattered most to them, no longer matter.

3) They are always complaining about the unfairness of it all, ill-treatment by others, etc. Today, they often post things on the Web (as Hasan may have). People provide warnings -- verbal or written complaints about the hopelessness of the world.

4) They begin to have frequent interpersonal conflicts with others. They become more tense and prone to feeling insulted or slighted.

5) Look for signs that they are making plans for the end (Hasan apparently cleaned out his apartment recently). They give away treasured objects, close bank accounts, etc.

Is there anything one can do to stop someone, once they have decided to do something?

Absolutely: A small intervention now can prevent huge tragedy later on. Someone has to recognize these signs. You have to give them hope beyond the tragedy that enrages them at the moment. You can turn them away from these crimes. Most people don't see the warning signs though -- there's a tendency not to see these changes in people. Friends can help people in these situations, but they usually need some professional help, as well. Professional help is the better choice.

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