Not long after Amy Bishop was identified as the professor who had been arrested in the shooting of six faculty members at the University of Alabama, Huntsville on Feb. 12, the campus police received a series of reports even stranger than the shooting itself.

Several people with connections to the university's biology department warned that Bishop, a neuroscientist with a Harvard Ph.D., might have booby-trapped the science building with some sort of "herpes bomb," police officials said, designed to spread the dangerous virus.

Only people who had worked with Bishop would know that she had done work with the herpes virus as a post-doctoral student and had talked about how it could cause encephalitis. She also had written an unpublished novel in which a herpes-like virus spreads throughout the world, causing pregnant women to miscarry.

By the time of the reports, the police had already swept every room of the science building, finding only a 9-millimeter handgun in the second-floor restroom.

But the anxious warnings reflected the fears of those who know Bishop that she could go to great lengths to retaliate against those she felt had wronged her.

Over the years, Bishop had shown evidence that the smallest of slights could set off a disproportionate and occasionally violent reaction, according to interviews with colleagues and others who know her. Her life seemed to veer wildly between moments of cold fury and scientific brilliance, between rage at perceived slights and empathy for her students.

Her academic career slammed to a halt with the shooting rampage against her colleagues. Bishop, 45, is accused of killing three fellow biology professors at a faculty meeting. Three others were wounded.

Her lawyer says that she remembers nothing of the shootings and that he plans to have her evaluated by psychiatrists.

Not the first outburst

The shootings took place after Bishop learned that she had lost her long battle to gain academic tenure at the university. But it was hardly the first time she had come to the attention of law enforcement because of an outburst or violent act.

In 2002, she was charged with assault after punching a woman in the head at an International House of Pancakes in Peabody, Mass. The woman had taken the last booster seat, and, according to the police report, Bishop demanded it for one of her children, shouting, "I am Dr. Amy Bishop!"

In 1986, not long after a family argument, Amy Bishop shot and killed her brother, Seth, 18, with her father's 12-gauge shotgun, putting a gaping hole in his chest and tearing open his aorta, according to the police report. She was 21 years old and, like her brother, a student at Northeastern University.

But Amy Bishop was not charged with a crime, and the shooting was never fully investigated by the police. She and her family said it was an accident, and the authorities accepted their version.

And in 1994, she and her husband were questioned in a mail bomb plot against a doctor at Harvard, where she obtained her Ph.D. and remained on and off for nearly a decade to conduct postdoctoral research.

In her earlier brushes with the law, Bishop emerged unscathed, and the University of Alabama, Huntsville never knew of them. But she left behind a trail of neighbors, colleagues and acquaintances who were mystified by her mood swings and volatility.

She yelled at playing children, neighbors said, and rarely kept her opinions to herself. She rejected criticism and fudged her résumé. Her scientific work was not as impressive as she made it seem, according to independent neurobiologists, some of whom said she would have been unlikely to even get the opportunity to try for tenure at major universities.

She was known to have cyclical "flip-outs," as one former student described them, that pushed one graduate student after another out of her laboratory. On the day she shot and killed her brother, she ran out into the street with the shotgun and demanded a car at a local dealership.

Dr. Hugo Gonzalez-Serratos, now a professor of physiology at the University of Maryland School of Medicine, collaborated with Bishop on a 1996 paper while both were working in the cardiology department at Beth Israel Deaconess Medical Center in Boston. When the paper was completed, Gonzalez-Serratos said, Bishop flew into a rage.

"She was very angry because she was not the first author," he recalled, referring to the more prominent position. "She broke down. She was extremely angry with all of us. She exploded into something emotional that we never saw before in our careers."

Even those who worked with her on fiction writing in Massachusetts described the experience as painful and said they always had a feeling she was about to explode.

"When I worked with her, I found she was always within striking distance of the edge," said Lenny Cavallaro, a writer who said he collaborated with Bishop on "Amazon Fever," the unpublished novel about the virus.

Some kind of dispute

On the morning of Dec. 6, 1986, there was an argument at the home of Judith and Samuel Bishop in Braintree, Mass., a middle-class suburb of Boston.

Judy, active in local politics, was out horseback riding. Seth was outside washing his car. Sam Bishop, a film professor at Northeastern University, was off to do some Christmas shopping. But before he left, he and his daughter, Amy, had some kind of dispute, according to police records. It was over something Amy had said.

Amy went upstairs to her room and would later tell the police that she had decided to load her father's shotgun. She wanted to learn how it worked, she said, because there had been a break-in at the house not long before.

Amy had never used the shotgun before. She loaded it and a blast went off in her room. Police later found evidence that she had tried to conceal the results of that blast, using a Band-Aid tin and a book cover to hide holes in the wall.

Carrying the shotgun, she descended the stairs to the kitchen, where her brother and mother were standing.

Judy Bishop told the police: "Amy said, 'I have a shell in the gun, and I don't know how to unload it.' I told Amy not to point the gun at anybody. Amy turned toward her brother and the gun fired, hitting him. Amy then ran out of the house with the shotgun."

Amy headed toward Braintree's commercial district, where Tom Pettigrew, who was working in the body shop of a Ford dealership, saw her walking around, looking into cars, carrying the shotgun.

"I kind of stepped back and said, 'What's going on, what are you doing here?'" Pettigrew said. "She said, 'Put your hands up.' I put my hands up and repeated the question."

He continued: "She was distraught. She was hyperaware of everything that was going on. She said: 'I need a car. I just got into a fight with my husband. He's looking for me, and he's going to kill me.'"

Minutes later, the police found Amy Bishop, still holding the gun. According to officer Ronald Solimini's report, she appeared frightened, disoriented and confused, and she refused his orders to drop the gun until another officer approached her from the other side. Police found one shell in the shotgun and another in her pocket.

Police officers began to question Amy, but her mother arrived and told her not to answer any more questions. Paul Frazier, the current police chief of Braintree, said that her release "did not sit well with these officers" and that the lieutenant in charge of booking that night told him a higher-up had given instructions to stop the booking process.

In an interview last week, the area's current prosecutor, William Keating, was highly critical of the handling of the shooting 24 years ago, particularly because it appears that Amy Bishop's actions after her brother's shooting -- demanding a car at gunpoint and refusing an officer's orders to drop the gun -- were not conveyed to state authorities.

Keating said Amy Bishop could have been charged with weapons and assault felonies, which would probably have prompted a psychiatric evaluation. Had such a charge, or any of the others that followed, been on her record, it could have changed the course of Bishop's career and the fate of those who died in Huntsville.

Instead, the investigation was stopped.

Did someone intervene to save Amy Bishop from prosecution? Her mother served on the town committee, an elected legislative panel of 240 members that set the town's spending. Or was Amy's release merely a small town's way of caring for its own? State authorities are now investigating.

Technically correct

The job application for the University of Alabama, Huntsville asked, "Have you ever been convicted of an offense other than a minor traffic violation?" Amy Bishop, who took a job there in 2003, answered with a simple "no."

Technically, she was correct. She was never charged with her brother's death, and though she was sentenced to probation in the restaurant incident, she was never officially found guilty. She and her husband, James Anderson, were questioned in connection with the mail bomb sent in 1993 to one of her mentors at Harvard, Dr. Paul Rosenberg, but nothing came of it. Authorities are now reinvestigating.

Bishop also arrived in Huntsville with a padded résumé, giving the impression that she had worked at Harvard two years longer than the university's records indicate. Still, with recommendations from Harvard and two other universities, Bishop did not attract scrutiny. At first, colleagues and students said, she came across as funny and extroverted, enthusiastic and knowledgeable about campus issues.

She was, however, not universally liked. Some students say they found her so unresponsive that they signed a petition complaining that, among other things, her test questions went beyond what was covered in class. Bishop would say, "Well, my daughter took it and she got an A, so you should be able to do it," said Caitlin Phillips, a junior studying nursing.

Graduate students did not last long in her laboratory, and those familiar with the department said that many transferred to a different one before completing their degrees.

But in 2008, Bishop seemed to be riding high. She and her husband had developed an automated cell incubator that was supposed to keep finicky cells, like nerve cells, alive longer and make experiments easier. The university, which would share in any proceeds, was trying to market the device, and the university president, David Williams, predicted that it would "change the way biological and medical research is conducted," according to the Huntsville Times.

Not strong enough

In March 2009, however, Bishop received word that her bid for tenure had been denied because her research and publication record was not strong, colleagues said. Such denials are rare, faculty members said, because the university reviews tenure-track professors annually, alerting them to areas that need improvement. Bishop appealed the decision.

"Her attitude was not, 'I'm going to have to go find another job,'" said Eric Seemann, an assistant professor of psychology. "It was more like, 'When are these idiots going to clear this up?'"

She lobbied for a re-vote in the department, badgering people for support, her colleagues said. In November, her appeal was denied. Increasingly expressing concern about her family's finances, Bishop hired a lawyer, her husband said, and filed a discrimination complaint against the university. He said she also began going to a firing range.

Her attorney, Roy Miller, said on Friday that Bishop does not remember what happened next. But the police and witnesses say that on Feb. 12, Bishop went to a faculty meeting with a plan. And a handgun.

"Her history speaks for itself," Miller said. "Something's wrong with this lady, OK?"