Speaking for the Dead:A Look at the Science of Forensic Investigation

Xenora L. Collins

What is Forensic Science?Forensic Science is defined as,The application of scientific principlesand methods to the investigation of crime.Put another way, forensic investigation allows us to examine and analyze a crime scene through the steps of the scientific method, and answer our own questions about who, what, when, where, and how the crime was committed. Sound interesting? Read on.

Narrowing the SpectrumNo thanks to TV series such as CSI and NCIS, forensic investigation has a new following, with a slightly Hollywood-ized twist. Despite Hollywood influence, shows like these incite curiosity.Forensics is a broad subject area. To narrow that subject, this project shall focus on one of the more popular studies in forensics, Bloodstain.

The ExperimentThe experiment will be to drop a solution of karo syrup and red food coloring to simulate blood from varying heights onto a piece of poster board. The resulting bloodstain will prove or disprove the hypothesis.

The ProblemWhen observing the crime scene, will the height of the blood source (i.e. victim or weapon) effect the diameter of the resulting bloodstain?

The HypothesisIf the blood source is further from the surface, then the resulting bloodstain will be of a larger diameter.

Materials

ProceduresNote: In this experiment I went only to six feet due to the height of my apartment.

Variables

Data & ConversionEach measurement is averaged from the four original stains to reduce the risk of human error.12inDiameter=.5cm Radius=.25cmArea=.25 x3.1415927=.20sq.cm24inDiameter=.75cm Radius=.38cmArea=.38x3.1415927=.45sq.cm36inDiameter=1.0cm Radius=.5cmArea=.5x3.1415927=1.76sq.cm48inDiameter=1.5cm Radius=.75cmArea=.75x3.1415927=1.76sq.cm60inDiameter=.1.25cm+spatter Radius=.62cmArea=.62x3.1415927=.1.20 sq.cm+spatter72inDiameter=1.5cm+spatter Radius=.75cmArea=.75x3.1415927=1.76 sq.cm+spatter

Graph

ConclusionHypothesis proven!

The Final Product

SourcesHallcox, Jarrett. Bodies Weve Buried: Inside the National Forensic Academy, the Worlds Top CSI Training School. Berkley Publishing Group, New York, NY. 2006. pg.181-189.

AcknowledgementsSpecial thanks to my mother, Lori Collins, for assisting in photographing the experiment and tolerating bloodstain in her kitchen, of all places. You were really a great sport!

***************