ForensicsForensicsThe Lovett School Seventh Grade UnitThe Lovett School Seventh Grade Unit

What is forensic What is forensic science?science?

• Application of science to law in events subject Application of science to law in events subject to criminal or civil litigation.to criminal or civil litigation.

Technical fields includes:Technical fields includes:

physics, biology, chemistry, engineering, physics, biology, chemistry, engineering, psychology, and medicinepsychology, and medicine

History of ForensicsHistory of Forensics

• It has been around for 900 years!It has been around for 900 years!

• Blood typing has been used since 1900, when Blood typing has been used since 1900, when blood types were discovered by Karl blood types were discovered by Karl LandsteinerLandsteiner

Suspect vs. Person of Suspect vs. Person of interestinterest

• Investigators consider someone a suspect Investigators consider someone a suspect once he/she becomes an official focus of the once he/she becomes an official focus of the investigation as a result of initial evidence or investigation as a result of initial evidence or circumstancescircumstances

• Person of interest – police can do initial Person of interest – police can do initial probing for information without initial probing for information without initial restrictionsrestrictions

Types of EvidenceTypes of Evidence

• FingerprintsFingerprints

• Blood splattersBlood splatters

• fibersfibers

• HandwritingHandwriting

• DNA samplesDNA samples

• Shoe printsShoe prints

• Insect or mold growth Insect or mold growth on bodyon body

• Gunpowder burnsGunpowder burns

• Bullet casingsBullet casings

Collecting EvidenceCollecting Evidence

FingerprintsFingerprints

• They are unique to each person, even They are unique to each person, even identical twins do not have the same identical twins do not have the same fingerprintfingerprint

• Loops, whorls, and archesLoops, whorls, and arches

Hair AnalysisHair Analysis

• Hair left behind at a crime scene is examined Hair left behind at a crime scene is examined for the structure (morphology) of the for the structure (morphology) of the individual hairsindividual hairs

• This evidence is not conclusive it is This evidence is not conclusive it is presumptive.presumptive.

• This means the hairs do This means the hairs do Not Not provide absolute provide absolute proofproof

• It helps to narrow down the suspectsIt helps to narrow down the suspects

• Conclusive tests are done next.Conclusive tests are done next.

DNADNA

• Longest lasting, stable evidence. Longest lasting, stable evidence.

• Researchers have uncovered usable DNA from Researchers have uncovered usable DNA from Egyptian mummiesEgyptian mummies

• DNA evidence is DNA evidence is

conclusive evidenceconclusive evidence

Karyotyping Karyotyping

DNA fingerprintDNA fingerprint

CSI effectCSI effect

The Body FarmThe Body Farm

• A A body farmbody farm is a is a research facility where human decomposition can be studied in a variety of settings.

• The The Body FarmBody Farm, the facility was founded in , the facility was founded in 1981 by Dr. Bill Bass, a professor of 1981 by Dr. Bill Bass, a professor of anthropology at University Of Tennessee. anthropology at University Of Tennessee. Before the Body Farm was established, Before the Body Farm was established, information on human decay was information on human decay was astonishingly inadequate, leaving criminal astonishingly inadequate, leaving criminal investigators poorly equipped for determining investigators poorly equipped for determining abandoned bodies’ time of death.abandoned bodies’ time of death.