Forensic Science covers all aspects of investigating a crime scene. Biotechnology has a part to play in a range of different areas.
DNA testing can be used to determine whether, for example, blood, hair, or other tissues have originated from a particular person. This gives a DNA profile of that person.
Analysis of intoxicants and other substances
Intoxicant (alcohol) levels in breath, blood, and urine may be tested as part of traffic and criminal investigations. Other work includes identifying substances that may cause similar symptoms as alcohol, and interpreting changes in alcohol levels in breath, blood, and urine in relation to time and the level of alcohol consumed.
Legal and illicit drugs which alter behaviour can be identified in blood, urine, and other body tissues, as well as in powders, syringes, and foods. This is known as forensic toxicology.
A wide range of biological, chemical, and magnifying techniques are used to identify small samples and allow comparison, for example of natural fibres, pollens, blood, paint fragments, etc.
Statistical interpretation of evidence
Many investigations involve comparisons between two samples (e.g. DNA from a particular person and DNA from a blood stain). If the samples match, it is important to be able to say whether it is (a) because of co-incidence or (b) because they came from the same source.
- 12 November 2007