What is Forensic Evidence?
This is evidence obtained by use of scientific methods and relied upon in a court of law. Forensic evidence can be anything and it can be found anywhere. You can use forensic evidence for:
- Identification – this involves classification of items. The expert assigns items to categories containing like items. He/she identifies objects by comparing their class characteristics with those of known standards.
- Individualisation – this refers to the demonstration that a particular sample is unique even among members of the same class. The expert demonstrates that a questioned piece of physical evidence and a similar known sample have a common origin. That is, in addition to class characteristics, you look for individual characteristics e.g. individualisation of persons through fingerprints.
- Reconstruction – this is the process of putting the ‘pieces’ together in a case or situation with the objective of reaching an understanding of the sequence of past events based on a record of physical evidence.
What is Forensic Science?
Forensic science is the application of natural science to matters of law. In practice, it draws upon principles and methods of traditional sciences such as physics, chemistry, and biology. It is concerned only with natural phenomena i.e. things and processes that are subject to observation, measurement and experimentation. Forensic science includes forensic medicine, toxicology, questioned documents examination, firearms, fingerprints examination, species identification etc.
Wildlife forensic science is science applied to legal questions involving wildlife crimes. Forensic science contributes to solving wildlife crimes through investigative activities. Such activities include determining the cause of wildlife death, identifying suspects, finding missing wildlife and profiling wildlife. In its simplest form, wildlife forensics seeks to link the crime scene, the suspect, and the victim. It does this in a way that is admissible in court.
Use of Forensic Science in Wildlife Crime Investigations
Morphology is the study of the size, shape, and structure of animals and plants and of the relationships of the parts comprising them. Specialists are often able to identify the species from its physical appearance. In addition to macroscopic features such as form, colour and texture, microscopic features can also be used. Morphology often relies on direct comparison with material in the reference collections.
This is the area of forensic science that deals with firearms, how they are used and why they are used. Ballistics studies the motion, dynamics, angular movement and effects of projectile units such as bullets, missiles and bombs. There are many applications of ballistics within a criminal investigation. The field of ballistics is able to identify rifling patterns, shell casings, powder burn, among others. It explores all areas relating to the use of firearms and the evidence they leave behind.
Most firearms have their own unique identifying features. Even if the suspect did leave the firearm at the crime scene, you can determine a lot of information from the bullet, the nature of the wound and any firearm residue. Further, the barrel of the weapon contains grooves which make marks on the shell casing. You can use the shell casings found at the scene as a means of identifying the make and model of gun used. Every firearm produces a slightly different and unique pattern on the shell-casing it fires.
You can use bullets recovered at a crime scene to identify the type of firearm. Ballistic experts usually study residue on the bullet and compare it to residue on the hand of a suspect, the gun that was fired, or any object that was close by when the firearm was used. Studying the markings found on a bullet or the impact a bullet made on any surface can establish exactly which gun the criminal used.
Forensic DNA gives the criminal justice field a powerful tool for convicting the guilty and exonerating the innocent. Scientists can use DNA to generate the profile of an individual or animal using samples from body tissues and products. The continued development and integration of wildlife DNA forensics will be critical for successful management of the many significant social and conservation issues related to the illegal wildlife trade and wildlife law enforcement.
Forensic Veterinary Pathology
Wildlife carcasses are a separate and unique type of forensic evidence which calls for the need of a forensic veterinary pathological examination. Forensic veterinary pathology is the study of disease or injury to animals for use in legal proceedings. It includes all types of damage caused by agents such as trauma, poisons, malnutrition, heat, cold, infections and other natural afflictions. In any investigation, the pathologist must determine whether the injury or death of the animal was the result of ‘natural’ events or caused by human intervention.
The pathologist carries out a post-mortem of the carcass to determine the cause and manner of death. A forensic veterinary pathologist will examine the carcass and during the exam, critical evidence may be recovered. This evidence may be able to provide essential information in cases of suspected illegal killings. In many cases, a suitably qualified and experienced forensic practitioner must carry out the examination if an incident results in a court case.
Forensic toxicology is the analysis of biological samples for the presence of toxins, including drugs. The toxicology report can provide key information as to the type of substances present in an animal. Toxins which lead to wildlife deaths include poisons, pesticides and fertilisers. Investigators use results of forensic toxicology to make inferences about a substance’s potential effect on an animal’s death or illness.
Forensic entomology is the study of the application of insects and other arthropods in criminal investigation. Decomposing carcasses usually have these insects or arthropods. The best-known example is the association of certain species of maggots or carrion beetles with carcasses. Experts use these insect colonizers to estimate the time, manner and cause of death of the animal. They also use forensic entomology to associate suspects with the death scene.
This is evidence created when two objects come in contact with enough force to cause an impression. Impression evidence includes fingerprints, footprints, tyre marks, cut marks and rifling patterns among others. Such evidence can help link a suspect or tool to a particular crime scene.
The examination of digitally stored records and information is a rapidly developing area of forensic examination. Computers, mobile phones, cameras and portable storage devices contain digital records. By examining this devices, investigators can determine whether you committed a crime, how you committed it, why you committed it, where you committed it, when you committed it and what your motive was.
Investigators often need to verify the authenticity or author of a printed or handwritten document. Such documents are known as questioned documents. Investigators have relied on questioned document analysis in wildlife cases, especially those involving import and export documents. It is usually in relation to documents that have been forged or altered. Document examiners use visual examination or advanced chemical analysis of inks and paper, to determine information relating to a questioned document’s authentication, authorship or creation date. They compare handwriting samples to determine whether the same person wrote them. They also compare questioned signatures with suitable reference signatures to determine if they are genuine or forgeries. Further, experts compare printed documents with the work of a particular printer. They also compare inks on documents and are able to identify entries written with a different pen.