The more we learn about accused killer Amy Bishop, the more University of Alabama-Huntsville officials need to worry about how they hire teachers and whether they bear a greater responsibility in this month's campus killing spree than originally believed.

Investigators of the Feb. 12 shooting that killed three university colleagues have discovered that Bishop's husband may have sent a pipe bomb to a doctor who gave Bishop a poor work review.

Bishop and her husband, James Anderson, were questioned in 1993, after Dr. Paul Rosenberg of Boston's Children's Hospital received a pipe bomb at his home. Weeks earlier, Bishop resigned from the hospital, due in part, to a poor evaluation Rosenberg gave her.

Rosenberg said he and others on staff believed Bishop was mentally unstable and could not handle her work load. He added that Bishop had "exhibited violent behavior."

The couple was never officially charged, but a witness to government investigators looking in to the attempted bombing, said Anderson wanted to shoot, bomb, stab or strangle Rosenberg in revenge for a poor work evaluation he gave her. The report also said Bishop was on the verge of a nervous breakdown.

Bishop remains jailed in Huntsville on a capital murder charge. And an insanity defense is likely since her attorneys are gathering results from mental exams.

But even if one believes Bishop and her husband weren't involved in the pipe bombing, there were several other violent outbursts in Bishop's background that should have made university officials pay attention and ultimately shred her job application.

In 1986, Bishop shot her brother to death. The shooting was ruled an accident, and she wasn't charged. In 2002, Bishop was arrested for punching a female diner in an argument over a booster seat.

I know of several people who were disqualified from employment for a lot less than shooting a sibling and being the prime suspect in mailing a pipe bomb to a colleague.

Why wasn't anyone connecting the dots in Bishop's violent past? It would have drawn a picture of a dangerous educator who should have been passed over for employment.