L1 Rich: introduction to forensic analysis Flashcards
what are 9 common types of physical evidence?
- Biological samples
- Organic substances
- Explosives, flammable materials
- Fibres, plastic, rubber, paint
- Glass, soil, minerals
- Wood and vegetative matter
- Documents
- Marks and impressions
- Digital information
what are the 3 steps of analysing physical evidence?
Recognition
Collection
Analysis
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?
threshold
what’s the limitation of quantitative analysis?
limits of detection
absolute accuracy
error limits
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?
- Spectroscopy
- 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