Forensic science is science used for the purpose of the law’ it has three main phases, which are, the recovery of evidence from the crime scene, forensic examination of the evidence at the laboratory and the presentation of evidence test results in court A crime scene is any location or locations which contain evidence that can help with a criminal investigation. Therefore, a crime scene can take many forms, it can be indoors or outdoors, i.e. a road accident or a burglary and it can consist of just a finger mark or it can include acres of land. Subsequently, many types of evidence can be found at a crime scene, from the smallest fibres which are invisible to the naked eye, to something as obvious as a broken window. It is up to the scene of crime officers to gather relevant physical evidence to send to the forensic laboratory for further examination Forensic laboratories are either provided within the police service (known as the forensic science laboratry department (FSL)) or by independent forensic services which offer different areas of expertise depending on specialist equipment and expert scientists in any given field Hence,
The crime scene is important because, if dealt with carefully, it can provide the physical evidence which is needed to build a criminal case against a suspect. The evidence recovered from a crime scene can be used in various ways, including: to establish if a crime has in fact occurred, as this is not always obvious at first glance, for instance, in the case of a fire scene it would need to be established if the fire was started either accidentally or deliberately; identification, evidence can help to identify the victim, offender and any other persons that may be involved in the crime; To corroborate or refute statements and to gather intelligence in order to make associations between different crime scenes and to find any links between the persons involved In order to produce such crucial evidence a crime scene is generally separated into two categories depending on the seriousness of the crime committed; less serious crimes such as burglary would be classified as a volume crime and more serious crimes such as murder would be classified as a serious crime, and so crime scenes which involve volume crimes are typically investigated by a lone scene examiner and serious crimes typically involve a team of scene examiners . Only reliable and impartial evidence can be used in court, therefore the evidence samples recovered from a crime scene need to be properly handled, preserved, packaged and transferred throughout the whole process of investigation. This careful process is known as the chain of continuity and needs to be demonstrated in order for the forensic laboratory to gain valid evidence which can be used in juridical proceedings
The forensic laboratory is an important part of the criminal investigation because it examines the evidence that is found at the crime scene and on victims and suspects, in order to find a link that can be used as expert evidence in court. Forensic examination aims to validate the evidence found at the crime scene with scientific proof that can withstand harsh cross-examining in court. Forensic analysis can support a criminal investigation in many ways, among others, it can prove that a crime has been committed, by identifying drugs or alcohol in a person’s blood stream, it can provide investigative leads, for example, by identifying a blood type or shoe size, and it can help identify a suspect via DNA in seminal fluid). Laboratories offer different fields of expertise depending on the many different types of evidence they examine For example, the toxicology and drug identification laboratory would be used to test drugs and poisons and the forensic serology laboratory would be used for the analysis of body fluids, such as blood and semen Therefore, the laboratory plays an important role in the investigative process, but unless due care and continuity has taken place to preserve the evidence at all stages of the investigation, i.e. preservation, documentation, storage and transportation, then the work carried out at the laboratory is discredited..