Flashcards in L1 Rich: introduction to forensic analysis Deck (24)
what are 9 common types of physical evidence?
1. Biological samples
2. Organic substances
3. Explosives, flammable materials
4. Fibres, plastic, rubber, paint
5. Glass, soil, minerals
6. Wood and vegetative matter
8. Marks and impressions
9. Digital information
what are the 3 steps of analysing physical evidence?
what does analysing physical evidence involve ?
Identification and comparison
what is identification?
determination of physical or chemical identity of a sample
what is comparison?
comparative analysis of a questioned and a control sample
what are class characteristics?
associated with a group (class) rather than with a single source.
what are individual characteristics?
properties that can be attributed to a common source with a high degree of certainty.
whats the limitations of qualitative analysis?
what's the limitation of quantitative analysis?
limits of detection
what are some physical characterisations?
• Temperature, mass, density, refractive index
• Physical state
• Microstructure and morphology
what are some chemical analysis ?
• Organic vs. Inorganic
• Qualitative vs. Quantitative
• Destructive vs. Non-destructive
• Bulk vs. Trace
• Presumptive vs. Instrumental
what are some analytical methods?
• Chromatography • Diffraction
• Microscopy and microspectroscopy
Name biological examples ?
semen, blood urine
Name organic substances?
car oil and cocain
Name explosives and flammable materials ?
Petrol, GSR, RDX, TATP
Name fibres, plastic, rubber and paint?
Name glass, soil and minerals ?
clay, sale , float glass, quartz sand, window glass
name wood and vegetative matter?
leaves, algae, pollen
Name documents ?
will, cheque, envelope
Name marks and impressions?
tool marks eg: crow bar, tyre marks, shoe impressions
banking, browser history, ip address, passwords
Ho many tests were done n the Sarah Payne case?
461 microspectrophotometry tests, 23 IR spectroscopy tests and 128 TLC tests
what are spectroscopic methods?
- Atomic emission