ABSTRACT
Joe Bryan, once a popular and respected high-school principal in a small Texas town, has been in prison for over 30 years. He is serving a 99-year sentence for the shooting and murder of his wife in 1985. Police investigators use blood pattern analysis (BPA) to work backward from blood traces at a crime scene, allowing them to reconstruct the locations and actions of the people and weapons involved. The traces include drips, smears, and spatters, which are created when drops of blood radiate from the impact of a bullet or blunt instrument until they encounter a surface and stain it. As the science of BPA progresses, a parallel challenge is to convert its results into new, practical, and transparent procedures for murder investigations and courtroom presentations. But BPA practitioners have not entirely welcomed these changes, which threaten to upset established field procedures, a reaction also found elsewhere in the forensics establishment.
