This report airs Dateline NBC Friday, June 4, 10 p.m./9 C.
It was a routine university faculty meeting hurtled into deadly chaos--in an instant.
STUDENT: I saw four stretchers come out with people on them...
The shooter? A woman -- and someone no one would suspect.
"The female shooter is Dr. Amy Bishop..."
Amy Bishop Anderson. Doctor Bishop, the brilliant, Harvard-trained biologist dedicated to her field.
IAN CAVANAUGH: Science is what excited her. Science really was Amy Bishop.
Professor Bishop, the sometimes difficult, sometimes nurturing teacher.
RENA WEBB: Very sweet, very open.
But she was a woman, as it turned out, with a past.
ARTHUR KERR: You got to watch out for Amy.
What led to the carnage in Alabama? To try to answer that question, Dateline has spent months investigating Amy Bishop, uncovering a series of strange and violent events and gathering the pieces of a puzzle that only now seems to make sense. What we learned raises the inescapable question: could it -- should it -- have been stopped? Our investigation begins in the hours just before the shooting broke out.
CHANTAI SIMMS: Went to her class, normal day, she seemed the same.
On Friday, Feb. 12, nursing student Chantai Simms attended Dr. Bishop's first class of the day at 10:20a.m.: Anatomy and Physiology.
CHANTAI SIMMS: Thinking back about it, I don't see anything different. She seemed the same.
Dr. Bishop's next class, Neuroscience, started at 11:30. And by now, student Rena Webb thought her professor was acting strange.
RENA WEBB: I didn't know if she was depressed or what her situation was. I don't know. Because she just wasn't her happy, normal self.
Dr. Bishop seemed extremely focused, concentrating with searing intensity.
And Rena, who usually sat in the classroom's front row, noticed something else in Dr. Bishop's tote bag.
RENA WEBB: And I saw the outline of a cylinder in the bag at the bottom of the bag.
Rena says when she saw Dr. Bishop move the object in the bag so no one could see it, she became puzzled.
RENA WEBB: Well, what you would be hiding in a bag? Why would you have to hide the shape of something?
At the time, how could Rena fathom that professor Bishop was allegedly in possession of a 9-millimeter Ruger handgun and several rounds of ammunition?
Around midday, Bishop apparently returned home to the two-story green clapboard house she shared with her husband, Jim Anderson, and their four children, ages 9 to 18. Anderson says he drove his wife back to campus that afternoon, dropping her off just before 3 p.m. so she could attend a faculty meeting. He was later asked about it on the fly.
CHRIS HANSEN, DATELINE NBC: And she said what about the meeting?
JIM ANDERSON: Nothing. Just a meeting. She's just got to go there, put in her time and then come home. I was going to pick her up and get a coffee.
CHRIS HANSEN, DATELINE NBC: So it was just a normal meeting?
JIM ANDERSON: Yeah, normal meeting. Normal Friday afternoon.
In a conference room identical to this one, on the floor above me, thirteen people from the biology department sat elbow to elbow around the conference table. Amy Bishop took a seat closest to the door. They talked about the next school year. Then the meeting started to wrap up.
Dr. Debra Moriarity was one of the thirteen.
MORIARITY: It's very near the end. I had to look down to write something up and I heard a loud -- a bang, a gunshot. And looked up and Amy was standing there with a gun and shooting.
Three professors were killed in an instant.
MORIARITY: My thought was she is going to go around the room and shoot everyone. It looked like she was just methodically going around the room.
Dr. Moriarity dove for the floor as more shots rang out.
In the midst of the unspeakable chaos, Moriarity scrambled on all fours beneath the conference table to the door and grabbed Bishop by the leg.
MORIARITY: I started yelling at her, you know, "Amy, you know, don't do this … Think about my grandson. Think about my daughter … Don't do this. Don't do this."
But instead of listening to Moriarity, she says Amy Bishop pointed the gun at her, and pulled the trigger -- click. The gun jammed. The two scrambled into the hall, and Amy aimed the gun again.
MORIARITY: It clicked again. Then there were a series of quick clicks. Then I just real quick, like, threw myself back -- crawled back in the room real quick and shut the door.
The survivors called 911 as Bishop took off. She allegedly went into a ladies' bathroom and hid the Ruger handgun in a trashcan under her bloodied coat. Student Sean Tate says she then walked into his lab class and urgently asked to borrow someone's cell phone.
State Trooper Brian L. Howe's report on the fatal shooting of Seth Bishop (pdf)
Braintree police department's report on the 1986 shooting (pdf)
Peabody Police report on the incident at the International House of Pancakes (pdf)
SEAN TATE: She looked anxious. A lot of anxiety in her eyes really. But other than that she just looked like a normal person.
CHRIS HANSEN: Maybe like she just had gotten some bad news and needed to make a phone call?
SEAN TATE: Yes, sir.
Jim Anderson got the call from his wife.
CHRIS HANSEN: What time did she call you?
JIM ANDERSON: Four o’clock. She's always pretty quick. Come pick me up, I’m done. I go to pick her up and I arrive to a sea of flashing lights.
Anderson says he didn't know what was going on, and neither did most of the campus.
CHANTAI SIMMS: It just went crazy, all of a sudden. Chaos.
Reporter: we don’t know about a shooter, we don’t know male, female, student, teacher, you just don't know right now.
And then the truth came into focus. It was biology professor Dr. Amy Bishop and the news stopped everyone in their tracks.
RENA WEBB: She just had this look on her face. Her eyes and her expression, it was completely different than anything I had ever seen.
CHANTAI SIMMS: I’ve never seen her look like that, ever. It was like something completely took over her.
The question now on everyone's minds: had they known more about Amy Bishop before the shootings, could the tragedy at UAH have been prevented?
In the aftermath of the shootings at the University of Alabama Huntsville, the school community tried to recover from the devastating loss in ways all too familiar now: flags at half staff; flowers and memorial signs; ribbons pinned on in honor of the dead.
Classes were cancelled for a week and in the void students and faculty found time to pray at a memorial service attended by thousands.
PRESIDENT: We come together to say farewell and to grieve for those we have lost.
Dr. Gopi Podila, 52, chairman of the biology department.
RENA WEBB: Oh, he was a wonderful human being. He was special because he really, he loved all the students.
Dr. Adriel Johnson, 52, an associate biology professor.
IAN CAVANAUGH: He really went out of his way to make sure that his students succeeded.
Dr. Maria Ragland Davis, 50, also an associate professor of biology.
PRANJAL HARAZIKA: Dr. Davis was very approachable, very open to ideas.
Seriously wounded and in critical condition that week were professor Joseph Leahy...
CHANTAI SIMMS: He's an amazing guy. I'm praying so heavy for him to recover.
And Stephanie Monticciolo, the biology department's assistant and all-round den mother.
RENA WEBB: You felt like it was a big family and you were part of that family being a student there.
While the university mended its wounds, across town Amy Bishop was on mandatory suicide watch at the county jail. And even though police had arrested her on the scene, Bishop was insisting to her attorney she wasn't at the shootings, and that they never happened.
ROY MILLER: She has no memory of it, and I have to take her word on that.
Weeks later, with Amy Bishop still in custody, Huntsville police paid a visit to the Bishop-Anderson home with a search warrant.
Jim Anderson, Bishop's husband: Well they weren't satisfied with getting my wife's computer, so they decide to take my computer, the girl's computers, ransack their underwear drawers.
Police located a suspicious-looking object on the property and brought in a bomb squad robot to blow it up.
NEIGHBOR: You could feel it in your chest when it went off, it's like "toof," you know.
It turned out to be a false alarm.
JIM ANDERSON: They found out a piece of equipment in the garage they didn't understand. It was a piece of PVC pipe and they had to blow it up.
While authorities were combing through Amy Bishop's home, others were wondering whether there was anything in Bishop's past that should have raised any red flags to UAH officials. President Dr. David Williams says there was nothing.
WILLIAMS: As far as her hiring was concerned, we obtained three letters of reference. And the letters that came were all favorable to professor Bishop.
When Amy Bishop was hired in 2003 it wasn't standard for UAH to do criminal background checks -- but even if it had, it wouldn't have mattered. Local police aren't talking, but Dr. Williams says right after the shootings, police ran a background check on Bishop and her record was clean.
PRESIDENT WILLIAMS: The Huntsville police actually did a criminal background check. And nothing came up. So, even had we done such a check back in 2003, one would presume also that the same results would've happened.
So what happened at UAH that apparently caused her to snap? Well, for one thing, anybody who knew Dr. Amy Bishop will tell you that in the last several years she'd been increasingly obsessed over one thing: tenure.
Tenure is the holy grail for any professor. Landing a tenured position at a university means you'll have a guaranteed job and a stable salary until you retire. And as the major breadwinner in her family, Amy Bishop certainly felt the pressure to get tenure at a school. She'd had five years to earn it at UAH, and the clock was now starting to run out.
Like many universities, UAH first considers a professor's teaching abilities. Some of Dr. Bishop's students we spoke to liked her.
RENA WEBB: She'd always have a big smile on her face coming into class. Very sweet, very open.
CHANTAI SIMMS: Personally, I always thought she was, like, a really brilliant lady.
But other students didn't appreciate her. What they saw as her bizarre tangents. Her superior air. Some reportedly even signed a petition against her.
But the university also evaluates tenure candidates on the research coming out of their lab, and in that arena Dr. Bishop seemed to be shining. She and her husband had developed an automated incubator to keep fragile cells alive long enough to study. The invention landed Dr. Bishop on the cover of a local technology review and the school's president crowed about the innovation.
But in March 2009, after a year-long review of her candidacy, Amy Bishop was denied tenure. The reasons haven't been made public, but UAH president Dr. David Williams stands by the decision.
WILLIAMS: Let me say that going to the bottom line, her tenure dossier, after extensive evaluation at all levels, simply did not meet the criteria that this university has for tenure.
Was the denial of Amy Bishop's tenure the key to the killings at UAH? Did she know that at least one of the professors in that conference room had voted against her in the tenure process? Had she been so enraged that she snapped in a way she never had before? Or was there more to the story?
There was a lot more indeed as we learned when we delved further into Dr. Bishop's past.
Two weeks after the shootings at the University of Alabama Huntsville that left three dead and three injured, the school sent Amy Bishop a terse letter firing her.
Amy Bishop's 20-year career in science ended in bloodshed and horrible disgrace. But did it have to be this way? The more we looked into it, the more we uncovered stories in Amy’s professional past that had never followed her. Problems which if UAH had known about, the school may have thought twice about hiring Bishop in the first place.
Amy Bishop started her academic career in science in Boston, Massachusetts, near where she grew up. In 1986, she was a biology major in college at Northeastern University, where fellow student Isabel Gomes remembers an overriding personality trait. Amy was so painfully shy she was almost invisible.
ISABEL GOMES: She just didn't interact with people. She didn't build any bonds at all. At all. And so, she became really easily forgettable, I think, and unnoticeable and unknowable.
But Isabel says Amy found one place she could fit in, one academic field that made her feel at home in the world: science.
ISABEL GOMES: I think that science was the one little slice of society where she actually thought and felt that she fit in. She had found a place where she was visible, a place where people would listen to her, a place where she felt comfortable talking about something, and that was science.
After college, Amy Bishop dedicated her life full-time to science, earning a PhD in genetics from Harvard in 1993. She then worked in various Harvard-affiliated labs, hoping for a tenured position that would provide financial stability for her growing family.
Those who know Amy Bishop from those years describe a woman intensely driven to succeed and determined to overcome any obstacles in her way.
Hard work is one thing, but we've learned that Amy Bishop was also involved in a series of volatile incidents before moving to Alabama.
One scientist remembers Amy Bishop exploding in an emotional outburst when she wasn't named first on this 1996 research paper.
Officials say Rosenberg is lucky to be alive. But there had been an even more troubling incident three years earlier in 1993. A suspicious-looking package had been mailed to the home of Dr. Paul Rosenberg, just a month after Amy Bishop had left Rosenberg’s Harvard-affiliated neuroscience lab.
POLICE: He saw wires in it. At that time he ran out of the house, got his wife. He took off out of the house, he called 911.
It was a deadly double pipe-bomb. The Bureau of Alcohol Tobacco and Firearms investigated.
FLUCKINGER: She was talking to the police, the police were investigating.
Lab technician Sylvia Fluckiger remembers Amy Bishop was having problems with Rosenberg during that time.
FLUCKINGER: It was common knowledge that they had an issue. That there was something that they didn't agree on.
In case files recently released by the ATF, Dr. Rosenberg says Bishop "could not meet the standards required for the work." Bishop allegedly feared Rosenberg was going to write her an unfavorable recommendation just as she was going to have to find a new job.
What's more, the ATF report also states someone heard Bishop's husband, Jim Anderson, say "he wanted to shoot him, bomb him, stab him or strangle Rosenberg."
Bishop and her husband were investigated for years but federal authorities never filed charges. Anderson says he never made those comments about Rosenberg. He denies that he sent the pipe bomb, and recently told NBC affiliate WAFF that he thought the case was closed.
ANDERSON: And then they just closed the case and sent everybody home.
CHRIS HANSEN: And you thought it was over.
ANDERSON: It was over. I have the legal paperwork that says it’s over.
The ATF is not commenting publicly. Meanwhile, the state's top federal prosecutor has ordered a review of the original investigation.
Whether or not Amy Bishop had anything to do with the pipe bomb, there was no mistaking her involvement in a disturbing incident at an International House of Pancakes in 2002.
Bishop walked in with her family to find that another mother had been given the last booster seat. According to police, she flew into an profanity-riddled tirade, announcing "I am Dr. Amy Bishop!" and punching the woman in the head. Bishop was charged with assault and battery. She was put on probation for six months, and then the case was dismissed -- so her name never went into the national criminal record database.
KERR: Punching people at IHOP for the booster seat. We heard about that one, but we just chalked it up as another example.
Arthur Kerr says he wasn't surprised about the IHOP incident. He and other neighbors of Amy Bishop's in Ipswich, Massachusetts say they'd suffered from Bishop's volcanic outbursts since the day she and her family moved in the mid-1990s.
KERR: When they moved in, they deliberately drove their moving van into the basketball hoop that was between our two driveways, and knocked it over.
And it got worse from there. They say Amy constantly screamed at kids and their parents about noise. Former neighbor Ryan Hopping remembers police once even had to break up a fight between Amy and another mother.
RYAN HOPPING: Amy Bishop really started screaming at the top of her lungs and went into this woman's face, face to face.
KERR: Next thing you know, Amy’s got her dukes up and she's ready to fight.
RYAN HOPPING: One of the officers screamed at Jim Anderson to get his wife inside the house. Told the other husband, the other woman to get her home or both were going downtown.
No one in Alabama knew anything about these incidents, these brushes with the law.
And of course they didn't know about another violent incident years earlier.
As you'll see, it happened not in the classroom, but in the kitchen of this house where Amy Bishop grew up and where someone died violently at her hands.
To fully understandwhat happened at the University of Alabama-Huntsville, you have to start a thousand miles away, in suburban Boston, at the childhood home of Amy Bishop. From the outside of this quaint Victorian house, there's little to suggest that the intense, intelligent but shy girl who grew up here was headed for anything other than the brightest future.
SUNNY SHAW: The Bishops were an odd family. But they were so talented we all kind of envied them a little bit.
Sunny Shaw was a neighborhood friend of the Bishops. She remembers Amy’s mother, Judy, as alternately gregarious and reclusive. Amy's father, Sam, was more reserved. And the Bishop children, Amy and her brother Seth, were uncannily alike. Both were top students with strong artistic talent.
SUNNY SHAW: Both of them were gifted musicians, and they loved playing the violin.
The siblings were also both socially awkward, but Seth’s sweet and empathetic nature won him a few loyal friends.
SUNNY SHAW: He's somebody you just remembered. Because he was so special. He was a magnificent student, a magnificent musician. He just was exceptional.
By the fall of 1986, the two siblings were both at Northeastern University. Amy was a junior, Seth a freshman. After only a few months on campus, Seth had already hit his stride. Sunny Shaw remembers running into him back at home at the end of his first semester.
SUNNY SHAW: And I asked him how he was doing. And he said, “Oh, Mrs. Shaw, I’m so happy at college.” And I said, “Oh, Seth, you look so happy.” And he said, “I am.” And I said, “Oh, that's great, honey. I'm so glad your time has come.”
But two weeks later, Seth Bishop was dead of an apparently accidental gunshot.
SUNNY SHAW: I thought, oh my god, it's not fair. He's finally found his voice. How can you take it away from him before he has a chance to use it?
That "accident" happened right inside the Bishop home in Braintree, Massachusetts. It was Dec. 6, 1986, a Saturday. Amy and Seth were both home for the weekend. It was around 11:30 that morning, and Amy Bishop's mother was due back soon from the local horse stables. Her brother was washing the car. Inside the house, Amy and her father got into an argument over something Amy said. She went up to her room, and her father left ... Leaving Amy in the house by herself.
Retired state trooper Brian Howe interviewed Amy back in 1986 about how that routine afternoon became a harrowing tragedy in an instant.
CHRIS HANSEN: What did she tell you?
BRIAN HOWE: She basically told us that she had been home alone at the time, she believed. That she had some concern for her safety. She indicated that there had been a break-in at their residence approximately a year before, which was the reason why her father had purchased a shotgun.
Amy said she wanted to learn how to load the shotgun. And went into her parents' bedroom to retrieve the powerful, 12-gauge pump-action firearm used for everything from home protection to hunting.
BRIAN HOWE: She took some of the shells, placed them in the shotgun, and then she couldn't figure out how to unload the shells.
Amy said when she tried to unload the gun, it "just went off" accidentally, blowing a hole in her bedroom wall and damaging a mirror. She tried to unload the gun again, but didn't know how.
BRIAN HOWE: At that point in time she said she heard her brother coming home downstairs.
Seth had brought in groceries for lunch then went into the living room to turn on the TV. He was on his way back into the kitchen where their mother Judy was, when Amy came downstairs with the gun.
BRIAN HOWE: She was trying to talk to her brother to figure out how to unload the shotgun. And she said in that discussion, her mother said something to her. She turned and the gun discharged.
Amy said she remembered her brother saying "oh god,” and heard her mother scream. Seth was shot. Amy fled the home. Judy called 911.
Braintree police officer Kenneth Brady responded to the call. To this day he remembers the heartbreaking sight of Seth Bishop lying on the kitchen floor in a large pool of blood.
BRADY: And it was a horrific wound. I mean his chest was just spread wide open. He couldn't have been more than three or four feet when the shotgun went off.
Seth Bishop was pronounced dead at the hospital less than an hour later.
SUNNY SHAW: Of course, we were absolutely in shock. All of us were in shock. And Judy said, you know, "it was a terrible accident." And so you believed it was a terrible accident.
But was it an accident?
On the morning after the shootings in Alabama this past February, a dawning realization settled over parts of eastern Massachusetts.
The shooter was one of their own.
MCCANN: it was horrible. It was so surreal. I looked at the picture and I said to it, "Amy, what did you do?"
A different sort of realization went through Tom Pettigrew’s mind when he saw a report on the Alabama shootings and saw a familiar face.
TOM PETTIGREW: I kind of jumped up and said "Oh that's the girl that me and my friend had a run-in with, you know, what is it, 23 years ago?”
That decades-old "run-in" may be the key turning point in the Amy Bishop story. As we discovered and you'll see, it was a moment that could potentially have changed everything.
It happened just after Amy Bishop shot and killed her brother in their family home. At the time, all almost anyone knew was that Amy had fled the house and was located by police shortly after. But Pettigrew tells a story that raises questions about whether the shooting was an accident and whether Bishop had fled in panic, or had something else in mind.
CHRIS HANSEN: This was back in 1986. But you remember it as if it were yesterday?
TOM PETTIGREW: Yeah, I do.
Back then Pettigrew was just another 22-year-old kid spending a Saturday afternoon working with his buddies at the body shop of a car dealership that used to be here.
PETTIGREW: We were outside. My friend was doing his brakes. And I looked over to this area and I noticed a girl with, at the time, I thought was a BB gun.
When he and another guy went over to check her out, he says he literally walked into the business end of a 12-gauge shotgun.
PETTIGREW: Bumped right into it. It kind of poked me right in the chest.
CHRIS HANSEN: that had to wake you up a little bit.
PETTIGREW: Oh, yeah yeah yeah.
CHRIS HANSEN: What did she say to you?
PETTIGREW: She goes "Put your hands up, I need a car.”
CHRIS HANSEN: “Put your hands up I need a car”?
PETTIGREW: Yeah, so we both put our hands up. And then I go "What are you doing here? What's going on?” And she relayed to me that she'd just got in a fight with her husband.
CHRIS HANSEN: With her husband?
PETTIGREW: Yeah. That he was looking for her, was going to kill her. She needed a car.
Pettigrew says that though he had no reason to doubt the girl's story, he also had no intention of either giving her a car or being her hostage.
PETTIGREW: She was definitely flipped out and definitely in control with the shotgun. She definitely was leading us around. She knew exactly what she wanted. And she knew what she wanted to do.
So when the right moment came he and his friend ran for cover. Minutes later, Pettigrew says, he saw Braintree police confront the girl on the street.
PETTIGREW: They're like all surrounded her. "Drop the gun. Drop the gun. Drop the gun." And it's like an easy 90 second standoff.
Only after another officer got the drop on her from behind did Amy Bishop put the gun down.
Even though Tom Pettigrew told all this to a Braintree patrolman at the time, nothing came of it. Amy Bishop was never charged with an offense for brandishing a gun or resisting arrest. But she reportedly was almost booked the afternoon she shot Seth--before something very unusual went down at the station.
KENNETH BRADY: Nobody was pleased with the way it was handled, least of all myself.
Former Braintree police officer Kenneth Brady told Dateline in his first extensive interview that he'd never seen anything like it in his career. It started when he brought Amy’s mother Judy down to the station where her daughter was being questioned.
BRADY: She immediately wanted to speak to the chief and I explained to her that the chief doesn't work on weekends. I think she knew the chief fairly well. She was a town meeting member. She had some position with the League of Women Voters. And I get the impression she knew him.
Brady left Mrs. Bishop in the lobby and went to check on the booking and says the officers were in the middle of figuring out what to charge Amy Bishop with.
BRADY: And we were deciding on what charges, what the charge would be. Would we be trying to go for the murder? Or do we want to go for maybe manslaughter? And we never got much far, much beyond that.
That's because the booking process was stopped, much to the surprise of everyone in the room. Brady says while he was in the booking room with the other officers, somehow Judy Bishop must have used a phone to call the chief, John Polio. Next thing anyone knew, Brady says, an order came down from Chief Polio: let Amy Bishop go.
BRADY: I believe he used the word -- he "forbids" you from booking her -- and to release her to the mother immediately, which is what we did. So I escorted Amy out to the lobby and her mother was there and they embraced. And the mother said, you know, "I’ve lost my son today and I don't want to lose my daughter also."
But apparently no one on the Braintree police force ever mentioned anything about Amy Bishop being let go that day or about her actions after the shooting. At least, they didn’t tell this man, former Massachusetts state trooper Brian Howe, who was the district attorney's lead investigator on the Bishop case.
CHRIS HANSEN: Were you given any details about Amy Bishop's activities after she left her family's house?
BRIAN HOWE: Only that she was located by officers from Braintree P.D. and transported to the Braintree police station.
CHRIS HANSEN: Were you told that she was carrying a loaded shotgun?
HOWE: No, I was not.
CHRIS HANSEN: Were you told that she pointed that gun at the chest of a worker at a car dealership?
HOWE: No, I was not.
CHRIS HANSEN: Were you told that she had to be told several times to drop the gun?
HOWE: No, I was not.
CHRIS HANSEN: Does that strike you as odd?
HOWE: It certainly does at this point in time, yes. I would have expected that I would have been provided with that information by Braintree P.D.
CHRIS HANSEN: How important were those details for you?
HOWE: Well, it's certainly something that I would have passed onto the district attorney's office, where a determination would have been made whether or not appropriate criminal charges should be brought forward. Obviously, not knowing that information I was never able to pass it to the district attorney's office.
CHRIS HANSEN: Do you think they were trying to protect Amy Bishop from potential criminal charges?
HOWE: It would appear someone was.
We wanted to know who, if anyone, was protecting Amy Bishop. Was her brother's death even an accident at all? And could the tragic deaths at the University of Alabama-Huntsville in 2010 have been prevented?
Had this investigation been conducted by the book, could three people in Alabama be alive today?
Within days of the shootings at the University of Alabama-Huntsville, current Braintree, Mass., police located and released more than 30 pages of original police reports from the Seth Bishop case. It's all in there: everything from Amy Bishop holding an auto mechanic at gunpoint and demanding a getaway car to her resisting arrest before being taken down to the police station.
But it's Amy Bishop's original statements that caught our attention first. We wanted to know just how believable is the story that she told police about how Seth Bishop was shot? Remember: she claimed that first the gun "just went off" in her bedroom, then she accidentally shot her brother in the kitchen.
I asked firearms expert Gary Woodworth to show me if it's plausible for a novice like Amy Bishop to have "accidentally" discharged the kind of shotgun her father owned -- not once but twice.
CHRIS HANSEN: There's no magic way this gun can go off without pulling the trigger?
GARY WOODWORTH: No.
CHRIS HANSEN: And that takes about five pounds of pressure?
GARY WOODWORTH: yes.
CHRIS HANSEN: And so, just by holding it like this, the weight of the gun should not go off?
GARY WOODWORTH: It shouldn't. It, you know, five pounds of pressure is a considerable amount of pressure.
Not only is it hard to pull the trigger on that kind of gun accidentally, Woodworth says that type of gun needs to be re-racked before it can fire again.
CHRIS HANSEN: So there's no way that you could fire this gun without chambering another --
GARY WOODWORTH: That's correct. That's correct.
CHRIS HANSEN: Just doesn't work any other way.
GARY WOODWORTH: Doesn't work.
We tested out the same type of shotgun -- a pump-action Mossberg -- to see just how powerful a firearm it is.
CHRIS HANSEN: If this gun was fired in a house--
GARY WOODWORTH: Very loud.
CHRIS HANSEN: Very loud?
GARY WOODWORTH: Very loud.
CHRIS HANSEN: You would hear it downstairs?
GARY WOODWORTH: You would hear it probably three houses away.
CHRIS HANSEN: Three houses away. If somebody did have an accidental discharge with that gun, it would be such a loud and frightening event that it doesn't make sense to you that they would then carry the gun around the house looking for help to unload it?
GARY WOODWORTH: No, no. I think probably in most cases, people would simply set the gun down and go for help to unload it, rather than to carry it to someone.
CHRIS HANSEN: Would it make sense that they would still be carrying around that gun and go walking through the house looking for help in terms of unloading the gun?
GARY WOODWORTH: It makes no sense to me.
It's just one of the things that makes no sense to anyone about what happened that day in Braintree, Mass., back in 1986. And as authorities today try to piece together exactly what went down in that 23-year-old investigation, there's been no small amount of finger pointing. The primary issue: why was Amy Bishop allowed to leave the Braintree police station without being charged?
Former Massachusetts District Attorney William Delahunt.
WILLIAM DELAHUNT: What is inexplicable is why did John Polio instruct the men that work for him to release Amy Bishop prior to notifying the state police. That's the $64,000 question.
Delahunt, now a congressman, says he doesn't know the answer. His former Assistant D.A. John Kivlan says what is clear is that in any event, it wasn't Chief Polio's call,
JOHN KIVLAN: It wasn't his decision to make. And Chief Polio knew that.
CHRIS HANSEN: Chief Polio overstepped his boundaries?
JOHN KIVLAN: That's correct.
CHRIS HANSEN: His authority?
WILLIAM DELAHUNT: Absolutely.
CHRIS HANSEN: He did not have the authority to release Amy Bishop that day?
WILLIAM DELAHUNT: That's correct.
JOHN POLIO: Well, I made no phone call, number one.
But former Chief John Polio, now 87, says he never made a call ordering the release of Amy Bishop that day. Instead, he says, his head of detectives (who is now deceased) recommended to him that Amy should be released, and that the case should be turned over to the D.A.
POLIO: Anybody that makes an inference there was a cover up, that is so far from the truth, I won't even get into it.
But the D.A.'s investigator, State Trooper Brian Howe, says he was kept so in the dark about the Bishop case by chief Polio's men that they never even gave him their case file.
BRIAN HOWE: I had asked a number of times for all of the Braintree reports as well as the photographs relating to this investigation.
CHRIS HANSEN: Were you given what you asked for?
BRIAN HOWE: I never received them, despite repeated requests on my part. They still were not forthcoming. We were told every time they were putting them together.
CHRIS HANSEN: "Putting them together"?
BRIAN HOWE: That's what we were told. Correct.
CHRIS HANSEN: Do you think they purposefully slow walked the reports and the crime scene photos?
BRIAN HOWE: Oh, knowing what I know now, they didn't slow walk it. They stone walled it. Those reports weren't forthcoming.
Howe says those reports were critical for knowing the full story. He says he even asked the district attorney's office for help getting the files -- but former Assistant D.A. John Kivlan remembers differently.
KIVLAN: That never happened.
CHRIS HANSEN: Never happened?
Congressman: Never happened. And had it happened, our office would've immediately caused those reports to--
CHRIS HANSEN: Jumped on it.
JOHN KIVLAN: --be summoned to the grand jury.
Howe stands by his recollection of events, but the former Assistant D.A. says reports or no reports, Howe didn't fully do his own investigation before concluding that Seth Bishop's death was an accident.
Congressman: Unfortunately, the second breakdown was compounded by trooper Howe not acting as he should as a state police officer. If you're conducting an investigation or you're responsible for conducting an investigation, you go to the police station, which he didn't do, you go to the autopsy, which he didn't do. It's really not about the reports as much as it is about the fact that he's responsible to conduct an investigation.
CHRIS HANSEN: Did Brian Howe drop the ball?
JOHN KIVLAN: I would expect better of trooper Brian Howe.
Former trooper Howe says once Amy and her mother were released, there was no reason for him to report to the station and that Braintree neglected to inform him about the autopsy, even though he'd asked to be alerted. Howe says even with all the new information that's come to light, he still believes Seth Bishop's death was an accident. But the current district attorney has questions and recently called an official inquest to sort it all out.
Keating press conference: The people in Alabama whose families are grieving over their loss deserve it.
Nineteen witnesses testified at the inquest, including Amy Bishop's mother, Judy. The findings haven't yet been made public, but the D.A. has also revealed an intriguing detail from the original Bishop case file: a photo of Amy Bishop's bedroom taken on the day of the shooting. The D.A. says if you blow up that photo, you can see a newspaper article lying on Amy’s bedroom floor.
The article, believed to be this December 1986 National Enquirer, reports how gunmen who killed actor Patrick Duffy’s parents nabbed a getaway car: breaking into "a car dealership" and stealing "a pickup truck that was in for service."
KEATING: The articles headlined in that newspaper so parallel the events that occurred that it goes directly to Amy’s state of mind at the time of the shooting.
CHRIS HANSEN: How significant is that?
KIVLAN: Well, obviously it's significant. It does provide evidence that this may have been an intentional homicide as opposed to an accident. It may have been a murder.
But whether or not Amy Bishop had been charged with murder or only lesser offenses in 1986, it begs the question: would the Alabama shootings in 2010 have happened?
CHRIS HANSEN: That's kind of a haunting notion. If she had been prosecuted in 1986 as--
DELAHUNT: Just simply on the felonies.
CHRIS HANSEN: --on the felonies.
CHRIS HANSEN: Could that have changed the course of history, and could three professors be alive today?
DELAHUNT: It clearly could have. What it would have triggered is a psychiatric evaluation of Amy Bishop, given her behavior during the course of the events surrounding the shooting.
KIVLAN: Even if she was treated in a prison setting, who knows. I mean, if she was released at some point, could something like this have happened someplace else, I don't know. But to answer your question, the likelihood is, she would not be a professor at the University of Alabama.
In March, Amy Bishop made her first appearance before an Alabama judge since the Huntsville shootings. She entered no plea, though her attorney has spoken of a possible insanity defense.
She is charged with capital murder and three counts of attempted murder for allegedly gunning down her biology department colleagues. If convicted she could face the death penalty.
And while Bishop - through her attorney - still maintains that her brother's death was an accident, the people of Alabama are left to wonder if the killings at UAH might never have happened if things had been handled differently in Massachusetts decades ago.
DELAHUNT: We're all human, and we all make mistakes. But this was a tragic mistake.
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