Two expert witnesses from the Pennsylvania State Police crime labs testified on Wednesday during Lawrence Earl Donachy's trial being held in the Elk County Courthouse. Donachy, 36, is charged in the April 6, 1999 rape and murder of Irene Challingsworth, a St. Marys beautician.
Forensic Lab Manager Bruce Tackett of the PSP Crime Lab in Erie, along with Forensic DNA Manager Beth Ann Marne of PSP Crime Lab in Greensburg, were both accepted as expert witnesses as part of the trial.
Tackett, who has worked in the forensic science field for over 27 years, specializes in serology, the study of blood and other bodily fluids.
In 1999, Tackett analyzed approximately 40 pieces of evidence in the Challingsworth case. He was requested to look for anything which might be foreign and could be linked to a suspect.
As part of the rape kit he analyzed, Tackett testified that no seminal material was found on swabs in 1999; however, the swabs were resubmitted by PSP-Ridgway for additional testing in 2002, which allowed him to utilize a new technique with more sensitive equipment which picks up lower levels of seminal fluid. As a result, he found semen present on the swabs.
He noted this technique was unavailable in 1999. The swabs were then sent away to PSP's Greensburg lab for DNA analysis.
Tackett said he reviewed the rape kit in July 1999 and at the end of 2002, with a report of the results issued in March 2003.
Among the items he analyzed which contained Challingsworth's blood were a piece of bloodstained carpet from the bedroom doorway; a pair of panties found near the foot of the bed; samples from walls surrounding her bed; three new pairs of panties with tags still attached containing small bloodstains found on them, which Tackett said were caused by impact splatter from her stab wounds; and a white pillowcase which contained heavy bloodstains on both sides.
Pick up a copy of the Thursday, Oct. 13, 2011 edition of The Ridgway Record for more.