Thursday, June 14, 2012

Courtroom Knife Wound Analysis Presents Challenges

by Andrea Campbell

In Urbana, Ohio, about 40 miles northwest of Columbus, a grisly murder took place in a rented duplex. Some dismembered remains of Jessica Rae Sacco were found in the shower. Gary Zerkle, the landlord, had been approached by Sacco’s mother who came looking for her 21-year old daughter after not hearing for too long. 

Zerkle took the key and went to check it out himself and once inside, encountered a locked bathroom door.

Jessica Rae Sacco
"I didn't think that was right," he said of the locked bathroom door. "Sometimes you get a gut feeling."

Reports say he removed the doorknob and pried open the door. It was the look behind the shower curtain that he wasn’t prepared for. "I pulled it back, and that was it," he said. "And I zoomed out the front door... I was trying to gasp for air."

Police say that Sacco had moved to Urbana from California the year before. The duplex she shared with her on-again, off-again boyfriend Matthew Puccio rented for $360 a month. In the latter part of the year, Andrew and Kandis Forney, of Fenton, Michigan, began staying with them.

Allegedly, Puccio had killed Jessica Rae Sacco by placing a bag over her head and suffocating her. The Forneys and yet another couple, Christopher Wright and Sharon Cook, of Urbana, are accused of helping with her dismemberment. Reports from police say that some of her body parts were found miles away in Kentucky.

According to an article for the Huffington Post about the intent, “Police would not discuss a motive for the killing, which they believe occurred around March 22. Police allege the Forneys, Wright and Cook were in the apartment when Sacco was killed but failed to intervene. Police say Puccio and Andrew Forney moved Sacco's body to the bathtub and dismembered it.”

Left to right: Matthew Starr Puccio, 25
Andrew Peter Forney, 26 (helped with dismemberment)
Kandis Jenniene Forney, 25 (helped cover up) Christopher Wright, 37 (cover up)
Sharon Cook, 25 (cover up)

Follow-up form the police chief said that Sacco, took classes at a local college and had only been in Urbana about a year after she moved there from California. He said Puccio had only been in Urbana a few months. Both were unemployed.

While the evidence in this case has multiple witnesses and overwhelming physical clues because of the dismemberment, typically the science used to identify knife and saw mark wounds, and the examination and its interpretation in bone has received little more than a cursory consideration in the forensic science industry.

History of Saw Mark Analysis
In the 1970s two science researchers attempted to introduce the topic of saw marks and toolmark analysis in bone to make it more useful to the field of forensic science. Wolfgang Bonte was one of the first who made a concentrated effort to more closely examine and describe saw mark striae in human bone. His casework however suffered limitations in that he failed to understand and recognize saw cutting action. 

In 1978, another scientist, R.O.Andahl attempted to describe saw cut characteristics in metal and animal bone, but his work in medicolegal cases of human dismemberment pointed up the need to analyze these characteristics more fully as his examples were often too simple and less than accurate. There needed to be an improvement in understanding not only the different areas of toolmark characteristics but to have a standardized way to describe forensically the principles of tool action in a cut.

Present Case Studies
The problem with today’s analysis is that there are many differences between knife cut wounds and saw mark analyses on cut bone. The ability to accurately describe in a court of law the features involving dimensions, the elements depicting wounds, and how to discriminate between different classes of saws and knives is still a tricky element. There is no standardization, meaning, it does not have “forensic standing” as a element of crime—it cannot pass Daubert evidentiary standards—and therefore testimony in that regard is just one person’s opinion. Steven A. Symes, Ph.D is the first researcher to publish a doctoral dissertation on the topic of saw mark analyses of cut bone, completed in 1992. He worked on and aided over 200 dismemberment cases involving approximately 700 to 10000 knife cut wound cases. Symes sees the diagnostic potential of developing a methodology to describe the features of cut wounds but it has yet to be implemented fully.

Problematic Terminology
Symes believes that since knife wounds are second only to ballistic injuries as the major cause of violent death in America, the widespread use of meaningless and misleading descriptors such as "sharp", "single-edged blade" and “hesitation mark" (which erroneously implies behavior) are common and may result in serious misinterpretation by attorneys, judges and juries.

The sharp force trauma that appears as an incised wound can be completed with any tool that has a sharp edge. Most of the incised wounds are created by some class of knife and are recognized as sharp force trauma. Most wounds are commonly termed a “knife stab wound” (KSW). But the term KSW is often misused, particularly by anthropologists, since most wounds they examine are without soft tissue.

Incised knife cut wounds are often described as wounds to the bone but are not necessarily due to stabbing. A KCW in bone is indicated when a sharp edged tool superficially incises bone while traversing over the surface of the bone. Symes thinks that forensic students are taught stereotypical adages when it comes to terminology. The difficulties with testimony fall on the fact that, “anthropologists and pathologists conduct numerous saw and knife mark analyses on dry and fresh bone, most professionals are reluctant to examine this bone within the soft tissue." In an article entitled Knife and Saw Toolmark Analysis in Bone, “the reasons for this avoidance include, but are perhaps not limited to: 1) difficulties in examining and transporting decomposed tissues, 2) a lack of equipment or training to process the remains after soft tissue examination, and 3) a general avoidance, 4) a lack of interest in the soft tissues in general, or finally 5) it’s just too damn difficult. Unfortunately, the situation often applies to forensic anthropologists and occasionally to medical examiners and coroners.”

So while the Sacco case might not hinge on knife wound analysis and toolmark evidence, this area of forensic science needs to be further examined and documented for standardized testing and ultimately, courtroom testimony.

Taphonomy – Edged, Incised, Hacking, and Impaling Traumas (Caution, photographs may be disturbing) 

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