Speakers
Description
From Scene to DNA: A Systematic Approach
to Bloodstain Pattern Analysis in Complex
Crime Scenes
Geetika Pant, Navyatha Shree, Karthick.S
Department of Biotechnology and Genetics, M.S.Ramaiah College of Arts, Science and Commerce -
Autonomous, Bengaluru
*Corresponding Email- geetika_biotech@msrcasc.edu.in
Bloodstain Pattern Analysis (BPA) is a forensic method that studies how bloodstains form
and where they are found to understand events in violent incidents. By examining the size,
shape, and spread of stains, investigators can identify the positions of people involved, their
movements, and the sequence of actions. In firearm cases, BPA can reveal where individuals
stood, how they moved, and how a weapon was used. Blood on a victim’s hands can
provide clues about weapon handling and firing positions in suspected suicides. To protect
evidence, the scene must be documented before gunshot residue (GSR) testing or moving
the body.Modern BPA goes beyond simple observation. Advanced techniques such as
probabilistic modelling and fluid dynamics consider gravity, air resistance, and droplet
deformation. These methods make it possible to accurately reconstruct how blood drops
travel, even over distances greater than one metre or in downward paths, improving
accuracy and reliability in complex cases.BPA examines various stain types, including
arterial spurts, cast-off patterns, and contact marks, while addressing challenges like
overlapping stains and environmental contamination. It can also guide DNA profiling when
samples are mixed or unclear.The process follows a systematic approach—starting with a
broad view of the scene and moving to detailed pattern analysis. It is performed by trained
professionals with expertise in injury biomechanics and experience in both crime scene
work and autopsies.When done with scientific precision, BPA is a valuable part of modern
forensic science, helping reconstruct events, confirm or challenge witness accounts, and
ensure correct interpretation of physical evidence in violent crime investigations.
Keywords: Bloodstain Pattern Analysis (BPA) , Forensic Reconstruction , Gunshot Residue
(GSR) , Injury Biomechanics , DNA Profiling.
