Generally speaking, forensic science is the application of any scientific knowledge to the law. It draws on principles and methods of traditional sciences as well as specific forensic science techniques such as anthropometry, fingerprinting, and blood stain analysis. Evidence gathered using scientific principles is prepared for submission in courts where it must be presented impartially, and the ultimate test is how well it stands up in court.
There are 10 lessons in this course:
The Nature of Forensic Science
Forensic Science and Law
Analysis of Evidence
Specialist Forensic Services
Psychological Disorders and Crime
Criminal Profiling and Intelligence
Presenting Evidence in Court
Each lesson culminates in an assignment which is submitted to the school, marked by the school's tutors and returned to you with any relevant suggestions, comments, and if necessary, extra reading.
Define forensic science and its various offshoots.
Describe the application of forensic science to the investigation of crimes and legal process.
Explain crime scene investigations, different categories of evidence, and their collection procedures.
Explain how different types of evidence are tested and analysed on site and in the laboratory.
Explain the roles of individuals working in specialist forensic sciences and the services they provide.
Understand theories underlying criminal behaviour in men, women and children.
Explain psychological disorders and how this can relate to criminal behaviour in adults.
Explain how assessment and data collection is used in forensic sciences, law enforcement and psychology to profile criminal offenders.
Understand how evidence is presented in court and issues surrounding eye witness testimonies.
Explain how ethical issues can influence collection of evidence, use of data and profiling.
Principles that Underpin Forensic Analysis
Forensic identification is based two main principles i.e. individuality and exchange.
The Individuality Principle
The principle of individuality as attributed to Paul L Kirk (1963) and is regarded as the building block for forensic science. Individuality implies that every entity, whether person or object, can only be identical to itself and so is unique. No two objects whether natural or artificial can be exactly the same. Kirk claimed that the aim of forensic science is to focus on the source of two items (questioned and known, or mark and print), which are thought to have come from a single source.
As such, identification is concerned with establishing individuality from traces left at a crime scene rather than the sameness of two things. This means identification can be shown indirectly through the analysis of traces and samples e.g. no two fingerprints are the same.
The Exchange Principle
The exchange principle is attributed to Edmond Locard. The principle states that whenever two objects or subjects interact, some sort of trace will be left behind. This is generally at the crime scene. Trace materials include hairs, blood, fibres, and gunshot residues.
Locard suggested that there are many traces left behind and if interpreted properly they provide the most valuable information.
There are some other more general principles which apply to forensic science:
The Law of Progressive Change
Different objects change, although they may change across different time spans. For example, blood samples will eventually degrade. Some objects are more durable than others and may be relatively permanent, remaining mostly unchanged during identification. If an object is very durable it may be quite easy use it for identification. If it is less permanent and its main features change during the identification process it is not possible to answer the question of sameness.
The Law of Comparison
Different samples must only be compared to samples which are alike. In other words blood samples are compared to other blood samples, fibres are compared to other fibres, and so forth.
The Law of Analysis
The quality of any analysis is determined by the quality of the sample under analysis, the chain of custody, and the expertise of the individual who analyses it.
The Law of Circumstantial Facts
This is concerned with eyewitness testimony, victim statements, and so forth. Anytime that people are called upon to provide evidence there is a chance that the evidence they supply is not accurate. This can be unintentional e.g. through mistaken observations, making assumptions or deliberate e.g. lying or exaggerating. On the contrary, evidence which gives a factual account e.g. based on investigation and evidence has a higher chance of being accurate and is more reliable.
Law of Probability
Conclusions drawn from forensic analysis are dependent on the method used and its advantages and disadvantages. This all has to be taken into consideration.
In conclusion, forensic analysis depends on both the discovery of traces, and connecting them to individuals. If there are no traces found at a crime scene, it is impossible to identify suspects. If traces are found then provided these are analysed properly and the results interpreted in a suitable manner, they may be used as evidence.
WHO CAN THIS COURSE BENEFIT?
- A crime writer wishing to produce more authentic fiction
- Security guards learning to be more observant of the property they guard
- Anyone working in a legal office seeking to better understand aspects of their work
- Investigative journalists seeking to expand their understanding of criminal activity
- Anyone considering a career in law enforcement or criminal law; to develop a fundamental understanding of the nature and scope of this subject prior to deciding on pursuing more in depth studies.
- Anyone else with a passion, or need to understand more about forensic science.