Ac 1.3 Criminology Personal Notes
Unit: Crime Scene to Courtroom 30 Minutes Name:
Topic: 1.3 Types of evidence
- Physical evidence
- Testimonial evidence
Process
- Collection
- Transfer
- Storage
- Analysis
- Personnel involved
Notes made during the lesson (in your own words)
Evidence can be put into two categories: physical evidence, such as tissues and bodily fluids
and testimonial evidence, which is spoken or written evidence from witnesses and suspects.
PHYSICAL EVIDENCE
Locard's exchange principle - can be applied to physical evidence. It says that whenever
somebody enters an environment (in this case a crime scene) something is removed as well
as added. Locard states “every contact leaves a trace”.
- Physical evidence can include tissues and bodily fluids (blood, semen, fingerprints,
saliva), impression evidence (tyre marks, bites, shoe prints) and trace evidence
(clothing fibres, glass fragments, paint). All physical evidence must be photographed
before it can be collected
- Before bodily fluids/tissues can be collected by CSI’s they must be air-dried to prevent
transference. After they have dried they are carefully collected and sent to forensic
scientists for analysis, this would ideally happen within 24 hours. Semen is typically
placed into a paper bag and is then put into a polythene bag which gets labelled.
Items such as skin flakes or hairs must be collected by professionals at the scene,
bagged, labelled and sent for analysis in the same way
- However, fingerprints are dusted with magnesium powder or an ultraviolet light is
shone onto them, this works for latent prints, after being photographed they can be
lifted with an adhesive strip and placed onto an acetate sheet. Patent prints can be
photographed and analysed for use in court, while plastic prints are also
photographed, CSI’s can make physical moulds of them
- Impression evidence may have casts made, for example teeth marks and shoe prints,
which can be later analysed by a forensic odontologist or the National Footwear
Reference Collection
- Trace evidence can help investigators place a suspect at the crime scene by
comparing fibres, paint, soils and glass fragments that were found on their person. As
well as this insects can also help determine the time of death, usually based on how
developed the larvae of blowflies are
Unit: Crime Scene to Courtroom 30 Minutes Name:
Topic: 1.3 Types of evidence
- Physical evidence
- Testimonial evidence
Process
- Collection
- Transfer
- Storage
- Analysis
- Personnel involved
Notes made during the lesson (in your own words)
Evidence can be put into two categories: physical evidence, such as tissues and bodily fluids
and testimonial evidence, which is spoken or written evidence from witnesses and suspects.
PHYSICAL EVIDENCE
Locard's exchange principle - can be applied to physical evidence. It says that whenever
somebody enters an environment (in this case a crime scene) something is removed as well
as added. Locard states “every contact leaves a trace”.
- Physical evidence can include tissues and bodily fluids (blood, semen, fingerprints,
saliva), impression evidence (tyre marks, bites, shoe prints) and trace evidence
(clothing fibres, glass fragments, paint). All physical evidence must be photographed
before it can be collected
- Before bodily fluids/tissues can be collected by CSI’s they must be air-dried to prevent
transference. After they have dried they are carefully collected and sent to forensic
scientists for analysis, this would ideally happen within 24 hours. Semen is typically
placed into a paper bag and is then put into a polythene bag which gets labelled.
Items such as skin flakes or hairs must be collected by professionals at the scene,
bagged, labelled and sent for analysis in the same way
- However, fingerprints are dusted with magnesium powder or an ultraviolet light is
shone onto them, this works for latent prints, after being photographed they can be
lifted with an adhesive strip and placed onto an acetate sheet. Patent prints can be
photographed and analysed for use in court, while plastic prints are also
photographed, CSI’s can make physical moulds of them
- Impression evidence may have casts made, for example teeth marks and shoe prints,
which can be later analysed by a forensic odontologist or the National Footwear
Reference Collection
- Trace evidence can help investigators place a suspect at the crime scene by
comparing fibres, paint, soils and glass fragments that were found on their person. As
well as this insects can also help determine the time of death, usually based on how
developed the larvae of blowflies are