DNA evidence can be collected from virtually anywhere. DNA has helped solve many cases when imaginative investigators collected
evidence from nontraditional sources.
Just as today's law enforcement officer has learned to look routinely for
fingerprints to identify the perpetrator of
a crime, that same officer needs
to think routinely about evidence that may contain DNA. Recent
advancements in DNA
technology are enabling law enforcement officers
to solve cases previously thought to be unsolvable. Today, investigators
a fundamental knowledge of how to identify, preserve, and collect
DNA evidence properly can solve cases in ways previously
seen only on
television. Evidence invisible to the naked eye can be the key to solving a
residential burglary, sexual
assault, or child's murder. It also can be the
evidence that links different crime scenes to each other in a small town,
a single State, or even across the Nation. The saliva on the stamp of
a stalker's threatening letter or the skin cells
shed on a ligature of a
strangled victim can be compared with a suspect's blood or saliva sample.
Similarly, DNA collected
from the perspiration on a baseball cap
discarded by a rapist at one crime scene can be compared with DNA in the
swabbed from the bite mark on a different rape victim.
Types of Evidence
- Impressions include fingerprints, tool marks, footwear, fabric impressions, tire marks and bite marks.
- Forensic Biology includes blood, semen, body fluids, hair, nail scrapings, blood stain patterns,
- Trace Evidence includes gun shot residues, arson accelerant, paint, glass and fibers.
- Firearms includes weapons, gun powder patterns, casings, projectiles, fragments, pellets, wadding and cartridges.
- Question Documents