The state's top federal prosecutor said today that the 1993 probe into a mail bomb sent to a Harvard Medical School professor was "appropriate and thorough," closing a review that she had opened after one of the original targets of the investigation, Amy Bishop, was charged earlier this year with slaying three colleagues at the University of Alabama.
Prosecutors and investigators "engaged in extensive efforts to determine the source of the incendiary device, but despite those efforts, were unable to gather sufficient evidence to bring charges. As a result, the matter was closed," US Attorney Carmen M. Ortiz said in a statement.
"This office does not intend to reopen the matter and we will have no further comment," Ortiz said.
Ortiz announced in February that she was going to take another look at the investigation, which had focused both on Bishop and her husband, Jimmy E. Anderson Jr.
The case began when two pipe bombs were mailed to the Newton home of Dr. Paul Rosenberg on Dec. 19, 1993. The Globe reported in February, based on sources and Bureau of Alcohol, Tobacco, Firearms, and Explosives documents, that, weeks before, Rosenberg had played a role in Bishop's resignation from her job as a postdoctoral research fellow in the hospital's neurobiology lab.
The University of Alabama case also prompted a review of the 1986 fatal shooting by Bishop of her brother, Seth, in the family's Braintree home. The review of that case, which was originally ruled an accident, led to an inquest into the death and then a grand jury indictment against Bishop on a charge of first-degree murder.
Bishop is charged with shooting three colleagues at the University of Alabama at Huntsville on Feb. 12.
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