Forensic Paint Analysis

Forensic Paint Analysis
How can paint tell a story??
 Able to associate an individual or
vehicle with a crime scene
 Hit and Run cases—dried paint/paint smears
transfers to clothing or vehicle upon impact
 Burglaries—paint can be transferred onto
tools used to break into things
 Can identify color, year, make, model of
a car by paint recovered at an accident
The vehicle
involved in a
hit-and-run of
a bicyclist who
later died left
white paint
chips at the
Paint is composed
of a binder,
pigments, and
different additives
Most paint is
applied in layers
Paint Layers on Vehicles
1. Electrocoat primer—applied to
steel body of car, provides
corrosion resistance, pigmented
2. Primer Surfacer—smooths out
and hides seams or
imperfections (different
3. Basecoat—color coat; different
additives add different effects
(pearl luster, metallic look)
4. Clear coat—unpigmented layer,
improves gloss, durability, and
How do we examine paint??
 Microscope
 Compare questioned
sample with control
(known) sample side by
 Determine type of paint,
 Look at surface texture,
color, and color layer
 Layers—each layer of
recovered sample is
compared with
corresponding layer of
the control sample
Forensic scientist using a microscope
to compare paint chips from a car
involved in an accident with known
samples of paint
Picture of paint comparison from hit and run
Malcolm Fairley
“The Fox”
 1970s British Serial rapist
 Detectives found yellow paint specks on a tree at one of
the crime scenes
 Paint analyzed—comes from a Austin Allegro car
 Narrowed suspects—detective drove up at Malcolm’s
house, found him cleaning a yellow Allegro
 Examined car—found scratches on paint that matched
paint flakes to the crime scene
 Using this and other pieces of evidence, Malcolm was
tried, convicted and sentence to 6 life sentences for
rape, assault, and burglary
Gary Ridgeway
“Green River Killer”
 1970s and 80s—truck painter who killed in Seattle
 Killed between 50-90 women and dumped in
Green River
 Gary was suspected but never arrested
 Killing stop and case goes cold
 2001—case is reanalyzed; paint on victims
clothing matched to highly specialized paint used
at Kenworth truck plant where Gary worked
 2002—using paint analysis as well as DNA analysis
Gary is found convicted of 48 counts of murder
and was sentenced to 48 life sentences

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