EXCLUSIVE: Ala. Shooting Suspect Amy Bishop's Husband: Tenure Likely 'a Factor'

The husband of the associate professor accused of killing three colleagues and seriously wounding three other people on an Alabama campus last week suggests the stress of her battle for tenure could have made her snap.

"Only someone who's been intimately involved in that fight understands," James Anderson told ABC News' "Good Morning America" of his wife Amy Bishop's alleged actions.

"It's a tough, long, hard battle," he said in his first sit-down, on-camera interview since the incident. "That, I would say, is part of the problem. It's a factor."

Though police have not declared a motive in the Feb. 12 shootings at the end of a University of Alabama in Huntsville biology department meeting, associates said Bishop was angry about having been denied tenure at the university.

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See more of Anderson's on-camera interview about his wife's alleged crime Friday morning on "Good Morning America."

In an earlier telephone interview with ABCNews.com, Anderson maintained the academic community at the university shares some of the blame for the shootings.

"I have worked around Ph.D.s before and they are pretty much the same," Anderson said. "Psychologically, they run hot and cold. That's why we are asking the news media to investigate that whole world that no one knows of. We are referring to an isolated group, like monks, and no one knows what goes on there."

However, the campus shootings are not the first violent crimes with which Bishop was involved. Her fatal shooting of her brother in 1986 was declared an accident. She was questioned, but not charged, during a mail bomb investigation in 1993. She admitted in court in 2002 that she punched a woman in an IHOP. And last year, some of her students petitioned to have her removed from the classroom.

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Anderson talks to Bishop for a few minutes daily on the phone, but as of Wednesday had not been allowed to visit her.

"She calls about the kids," Anderson earlier told ABC News. "Are they doing their homework?"

Their four children, aged 8 to 18, are aware of their mother's arrest, Anderson said, though the youngest one doesn't fully comprehend what it all means.

'She Pointed the Gun at Me and Pulled the Trigger'

Whatever the reason for the shootings, a woman considered Bishop's best friend on campus told ABC News' "Good Morning America" this week that she saw Bishop pointing and firing a gun at the staff meeting, and may have survived only because the gun evidently jammed or ran out of bullets.

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Debra Moriarity, 55, a professor with a lab next to Bishop's, said she pleaded for her life.

"I know I yelled at her, 'Amy, think about my grandson, think about my daughter," the Alabama professor told "GMA."

Moriarity said her friend was unmoved by her pleas.

"She ... pointed the gun at me and pulled the trigger. And it clicked and clicked again. She moved around a little. Click," Moriarity said. "I'm here talking to you today because the gun didn't fire."

VIDEO: Amy Bishops husband cites stress from tenure battle as a factor in the attack.Play
Alabama Shooting Suspect's Husband on Campus Killings

New details also emerged this week about Bishop's killing of her brother, Seth Bishop, 18, in Braintree, Mass., in 1986.

The shooting at her family's home was deemed an accident and Bishop was not charged. But records show Amy Bishop was armed with a shotgun and crouching behind a car when she was taken into custody.

"I drew my service revolver and yelled three times drop the rifle," Officer Timothy Murphy wrote. "After the third time she did."

The incident provided probable cause to file weapons and assault charges against her at the time, police said, according to The Associated Press, but charges were not filed and the statute of limitations has expired.

Bishop also was questioned, and again never charged, in a 1993 attempted mail bombing of a Harvard professor.

Amy Bishop Punched a Woman Over a Restaurant Booster Seat

In 2002, Bishop admitted in court to punching a mother in the head after the woman was given the last booster seat in an International House of Pancakes restaurant in Peabody, Mass., the AP reported.

Bishop apparently wanted a booster seat for her own young child and yelled at the woman, "I am Dr. Amy Bishop," according to the police report.

Peabody police Capt. Dennis Bonaiuto said Bishop admitted to the assault in court and the case was adjudicated, meaning the charges eventually were dismissed.

Finally, in 2009, dozens of Bishop's students signed a petition to remove her after appeals to school administrators failed to get her out of the classroom.

One of the letters was addressed to the biology department chairman, Gopi K. Podila, but in a subsequent meeting with the students Podila dismissed their complaints, student Caitlin Phillips told the Associated Press. Podila was the first person shot when Bishop allegedly began her shooting spree last Friday.

In at least three complaints to administrators, the students said Bishop had unsettling ways, never looked students in the eyes, and frequently talked about her alma mater, Harvard University.

"We could tell something was off, that she was not like other teachers," Phillips told the AP.

ABC News' Susan Donaldson James contributed to this report.