Damel Burton, 34, got on the Queens Q111 bus on Dec. 2 convinced the other passengers were after him. He was carrying a pistol, too. Not long before he had used it to shoot his girlfriend's son, Keith Murrell, 18, in the chest, ending his young life. Asked by Crimes of New York, the police said they still don't know why.

This type of homicidal rage is not what usually goes through the mind of most individuals with paranoid delusions, say the experts. But it does happen to a few--the ones so consumed with fear that they are driven over the edge-to homicide. Experts, just like the police, may never really know-but they can attempt--to understand what went through Burton's mind that day.

The results of Burton's thinking that mostly cloudy, 50-degree afternoon, were grimly clear. In about 15 minutes, he murdered two people, wounded another, and sent terrified passengers on the bus running in terror --in fear for their lives.

Burton, whether found sane or not, will doubtless return to prison or a hospital and spend the rest of his unhappy life there.

Police officials say Burton's rampage began with the shooting death of Murrell and continued when he boarded the Queens bus and shot Marvin Gikes, 36, in the back of the head and Jojuan Lipsey, 29, in the face. Lipsey survived . Gikes was not so lucky.

Reports from the Daily News indicate that Burton had become increasingly irrational after a seven year stint in prison for armed robbery. Other reports from news sources indicate that Burton had a history of paranoia, which possibly contributed to his violent rampage. Families are left clinging to the memories of their loved ones as police begin to put the pieces together as to why this tragedy occurred.

According to Dr. Liza Gold , a clinical professor of psychiatry at Georgetown University Medical Center  in Washington, D.C., what happens to delusional individuals like Burton, is that they come to believe they are acting in self-defense.  Gold  is the Vice President of the American Academy of Psychiatry and the Law--a professional organization for forensic psychologists and psychiatrists across the country. If reports of Burton's paranoia are accurate, it seems pretty clear that the victims on the bus were tragically just in the wrong place at the wrong time.

After the chaos, Burton had claimed that some of the passengers on the bus, including Gikes, were talking about him.

Dr. Gold said paranoia delusions can be triggered by a real or perceived event. His killing of Murrell before stepping foot on the bus may have been such a trigger--causing his delusions that innocent bystanders were talking about him and possibly after him.

 The reason they act out violently is because they are afraid, said Gold. They think of it is self-defense. Gold has had dealings with paranoid and delusional individuals before. She said that someone who suffers from paranoia may have a heightened sense of fear, especially after they have committed a crime. Gold also noted that it becomes difficult for these individuals with paranoid delusions to see things any other way. They become so convinced that people are after them--that people are trying to get them--that it completely consumes their lives.

You couldn't convince these people that they were ill, said Gold. Therefore, these people are extremely difficult to treat. Unfortunately, it seems likely that Burton became so immersed in his delusions that, To him, they were not random civilians. He has identified those people as a threat. Adds Gold. Most of these people know they have done something wrong. These are folks that know it is wrong to kill. They consider it a self-defense thing.

That said, Gold stresses that mentally ill people are not usually like Burton. It's a common myth, that people with mental illness are more violent other people, She stresses.

In her experience it is more likely to be just n the opposite--people suffering from delusional paranoia or other mental illnesses are actually more likely to be scared of interacting with other people. They tend to run away from them.

As an example, she cited a case in which a seemingly normal mother with a loving husband and child, believed she was being stalked by her gym trainer. This proved to be untrue, but Gold notes the woman had left her family and home because of her delusions. Gold says it's more common for people with mental illnesses to attempt to leave society, so to speak, rather than act out maliciously.

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