The Use of Contextual Information in Forensic Investigations - Essay Example

The Use of Contextual Information in Forensic Investigations Name Institution Introduction Most of the forensic fields need some forensic specialists to inspect extensively whether two pattern evidences are identical before concluding a match (Miller, 2005). These forensic specialists and experts need to reinstate their conclusions and decisions on the contextual information applicable to the task at hand and free from any kind of bias. Research studies have focussed their attention on the factors that influence perception and judgement with regard to forensic investigations (Dror, Charlton and Peron, 2006). One growing concern when it comes to forensic investigations is contextual bias that makes conclusions and observations to be deluded by superfluous information. Forensic studies have reported that contextual bias is a huge concern that has the ability to undermine the reliability of forensics. Since forensic is considered a complex interrelationship between justice law and science, possible conclusions may signify that some genuine evidences may be neglected which result in innocent people being convicted or guilty people being acquainted (Dror, Charlton and Peron, 2006). Contextual information is necessary in forensic investigations as it allows for the right decisions to be made. This report will discuss the use of contextual information in forensic investigations and will make use of case studies in illustrating this. The Use of Contextual Information in Forensic Investigations In the context of forensic investigation, when a forensic analyst is given a sample from the crime scene to test and analyse, they often receive information about the sample they are analysing and its perspective (Wood, 2003). This information may be in terms of the crime, the location of the sample, the name of the suspect, and the expected results among others. Most of the times, this information has a huge influence on the investigation. Physical evidence is considered the expected results of any crime scene investigation that is able to offer conclusions and decisions (Wood, 2003). However, before physical evident can be used, it should be collected in such a manner that none is destroyed or contaminated, it should be admissible as evidence and best serves the judicial process. Physical evidence can be termed as any information that can establish whether a crime had been committed or not (James and Nordby, 2005). According to the locards principle, when two entities come into contact with each other, there is always transference of material and content between the two. Forensic evidence acts as a source of contextual information in forensic investigation (James and Nordby, 2005). The evidence does not lie, cannot be questioned and is not influenced by personal and media views and sensationalism of the crime. In addition, physical evidence is recognized in court as true and indubitable. Information that is used in assisting the determination of physical evidence come from investigating officers, scientists, witnesses and initial scene examination (James and Nordby, 2005). Physical evidence maybe in the form of shoe marks, body tissues, blood, chemical enhancements, saliva, hair samples, semen and fibres among others. Shoemarks may be seen in a crime scene and may be used in solving such a crime. In order to be able to draw conclusions from such evidence, there is need to identify the footwear impression in the crime scene (Kassin, Dror and Kukcka, 2013). In addition, the analysts should locate identical footwear with the same impression and carry out a comparison to determine whether they correlate in characteristics. This information from the comparison of the footwear impressions will then be interpreted correctly in order to corroborate or disprove suspects (Kassin, Dror and Kukcka, 2013). On the other hand, the pattern, genetics and location of blood stains may also be used to retrieve important contextual information that may assist in an investigation. Non-destructive methods of enhancing blood stains are used such as polilight and oblique lighting. Evidence of similarities between the characteristics of the blood stain and the suspect may yield important information regarding the innocence or guiltiness of the suspect (Kassin, Dror and Kukcka, 2013). When gathering contextual information about a crime, there are many parties involved (Found and Ganas, 2013). For instance, there is need for patrol officers who serve as crime scene technician, laboratory scientists who offer their technical and scientific knowledge in solving crimes and crime scene technicians who act as civilian personnel. Police, laboratory technicians, prosecuting authorities as well as pathologists act as a collaborative team in forensic investigations (National Research Counclil, 2009). In forensic investigations, forensic scientists need to consider what information to include and what not to include when coming up with conclusions from physical evidence (Stoel et al., 2015). The facts to be included in concluding physical evidence is contextual information. Forensic scientists are known to only use the task-relevant information when doing forensic investigations. There are some guidelines that have been established in order to differentiate between task-relevant and task-irrelevant information (James and Nordby, 2005). The relevance of information used in forensic investigation is achieved if it is able to draw conclusion about the physical evidence designated for examination. Information is task-irrelevant if it impossible to draw conclusions from the physical evidence designated for testing. Forensic scientists are unable to carry out their tasks without contextual information (James and Nordby, 2005). Forensic scientists require contextual information so as to do their task in crime investigation (Osborne et al., 2014). For instance, when examining fingerprint, an examiner requires information about the surfaces and faces from which the fingerprints were retrieved so as to examine and determine whether inconsistencies between fingerprints may have been triggered by distortion of any of the planes. Also, when analysing blood during crime investigation, a blood pattern examiner may require information of the whereabouts of the blood sample so as to determine how it was deposited there (Osborne et al., 2014). Whether such information is relevant during forensic investigation depends on its ability to assist in drawing accurate forensic conclusions from physical evidence (Osborne et al., 2014). Any information that is helpful to a forensic scientist when assessing the strength of connection between evidence and propositions is considered relevant contextual information (Osborne et al., 2014). Many forensic scientists are often exposed to contextual information that assist them process and interpret physical evidence. Exposure to this information assists in the interpretation of the physical evidence in question. Without contextual information it is impossible to draw conclusions on forensic investigations (Osborne et al., 2014). In order to solve crimes, evidences are required to be presented in court for judgement. These evidences need to be supported by relevant contextual information in order for judgement to be passed. In order for any physical evidence to be relevant in solving crime investigations, it needs to be identified, captured, inspected and eventually presented in court. In many countries, according to the established jurisdictions, forensic scientists work following a constant crime scene investigation model (Osborne et al., 2014). And for a conclusion to be passed there is a need to detect, preserve and present evidence using relevant contextual information. This should be done in a manner that is responsible and serve the judicial outcome. For instance, footwear impressions are often overlooked as a way of retrieving necessary information required in identifying an offender at a crime scene (Risinger et al., 2002). Many forensic scientists’ rely on traditional means such as fingerprints and DNA in gathering information about a crime. Nevertheless, footwear impressions are as powerful as other forms of physical evidence. Forensic scientists need to be aware of the power of information retrieved from footwear or tyre impressions (Risinger et al., 2002). A case study that can explain the role of footwear in forensic investigation involves murder case in Australia (Dror, Charlton and Peron, 2006). In 2004, there was a dead body found in the changing room in Fremantle Park. According to investigations conducted on the body, the person suffered from excessive head injury (Dror, Charlton and Peron, 2006). In the crime scene, there was a large amount of blood on the floor. When forensic investigations started, there was no observed shoe outsole in the blood stains. In order to assess the case and draw some conclusions, there was information required. At post mortem, there was evidence of overlapping shoe outsole in the blood stain (Dror, Charlton and Peron, 2006). In addition, a brand name of the outsole was identified in the shoe impression. Amido black was used to enhance the shoe outsole impressions which were finally identified. The same day, persons of interests were located who were wearing the shoes with the impressions of “Danger Zone” which was identified in the crime scene (Dror, Charlton and Peron, 2006). The next year, forensic scientists carried out a comparison between the shoes seized from the persons of interest and the shoe outsoles retrieved from the crime scene (Dror, Charlton and Peron, 2006). Their characteristics were compared and it was identified that the two had class characteristics in common. This evidence of the commonality between the shoe outsole impressions was presented in court and the persons of interests were found guilty of the crime and were sentence to death. If the shoe outsole impressions were not enhanced using Amido Black, the evidence would not have been realised (Dror, Charlton and Peron, 2006). In the case study, in order to draw conclusions from the murder, forensic scientists were required to retrieve some contextual information from the physical evidence. The first information that assisted in solving the murder case was the information about the shoe outsole impression in the crime scene (Dror, Charlton and Peron, 2006). In addition, the second important information was gotten from the comparison of the outsole impressions from the crime scene and those from the persons of interest. This was able to confirm the involvement of these people in the murder of the man. This case illustrates the importance of contextual information in drawing conclusions from forensic investigations (Dror, Charlton and Peron, 2006). In addition, contextual information is said to affect the relevant probabilities and the strength of inferential connection between physical evidence and relevant propositions. It assist in coming up with suggestions about the examination of physical evidence through the use of correct analytic method (Found and Ganas, 2013). Any suggestions and conclusions that forensic scientists draw from this contextual information are beyond their scientific expertise and are examined by the justice system in solving crimes. Sometimes the information used by forensic analyst may be irrelevant in solving the crime in question (Found and Ganas, 2013). As mentioned earlier, for contextual information to be relevant and valuable in solving crime investigation, it needs to have the ability to draw conclusions from examined physical evidence. In order to identify the use of contextual information, let us consider some information involving fingerprints examiner who is expected to evaluate and examine whether a fingerprint at a crime scene is from a given suspect (Dror, Charlton and Peron, 2006). There are several contextual information that may be linked to this type of case study; for instance contextual information about the criminal history of the specific suspect. Often, forensic analysts have history of suspects and may be drawn to using them. However, in this case, the history of the suspect is not required in drawing conclusions from examined physical evidence and for this reason; it is considered irrelevant (Dror, Charlton and Peron, 2006). The second contextual information may come from the confession to the crime. When a suspect confesses to the crime, the information may be used to draw conclusions to involvement in the crime. However, it does not involve comparison or evaluation of the fingerprints in the crime scene and therefore does not meet the requirement of relevant contextual information (Dror, Charlton and Peron, 2006). It only classifies as a conclusion that does not need any fingerprint comparison. Information that involves the evidence of fingerprints at the crime scene is relevant contextual information (Dror and Charlton, 2006). This information confirms through examination that there is a comparison between the fingerprints of the suspects and those of the fingerprints found in the crime scene. Fingerprint examiner is required to draw conclusions by comparing fingerprints rather than just reasoning about whether a suspect was involved in a crime (James and Nordby, 2005). Reasoning may lead to contextual bias. The rise in contextual bias among forensic scientists has raised concern in crime investigations. Forensic research has shown that forensic analysts are highly influenced by information that is irrelevant to a particular case. Contextual bias results when evaluations of crimes involve subjective elements or when the information used is irrelevant to their given task (James and Nordby, 2005). Therefore, in order to be able to draw correct conclusions from a crime scene, forensic scientists are required to use relevant contextual information. The use of use of contextual information in crime investigation may lead to contextual bias. For instance, the Madrid train bombing which took place in 2004 represents an example of the inaccurate fingerprint identification as a result of contextual bias (Dror and Chalton, 2006). The case involved different parties such as the police, scientists and judicial system. The police gave images of partial fingerprints that were retrieved near the crime scene from bags of detonators (Found and Ganas, 2013). From the fingerprints presented to the FBI, the bomber was identified as Brandon Mayfield. This information was confirmed by other fingerprint experts appointed by the court. However, through remarkable circumstances, errors were found from the fingerprint result. The error was not as a result of methodology of technological use; it was human error. The pressure from the circumstance having been a high profile case influenced the fingerprint examiners (Osborne et al., 2014). In addition, overconfidence also may have contributed to the errors in comparing the fingerprints. In order to determine the final verdict, other examinations were carried out and the fingerprints were compared again. Brandon was later vindicated by the correct fingerprint evidence (National Research Council, 2009). This case illustrates that in order for contextual information to draw correct conclusions about a forensic investigation it needs to be relevant to the specific crime case. Conclusion In conclusion, a forensic investigation involves identification of the crime scene, collection and examination of the physical evidence and presentation of contextual information to the justice system for verdict to be passed. Forensic specialists are used to inspect extensively whether two pattern evidences are identical before concluding a match. In order for this to be possible, there is a need for evaluation of physical evidence retrieved from the crime scenes. Evaluation of physical evidence yields information that is necessary when drawing conclusions about a crime investigation. Physical evidence may be in the form of shoe marks, body tissues, blood, chemical enhancements, saliva, hair samples, semen and fibres among others. The facts to be included in concluding physical evidence is contextual information. Any information that is helpful when assessing the strength of connection between evidence and propositions is considered relevant contextual information. Contextual information is able to assist in the investigation process and interprets physical evidence. Also, contextual information impacts the strength of inferential connection between physical evidence and relevant propositions. In general, it assists in developing conclusions and suggestions about physical evidences which are presented in court for verdict to be passed. References Dror, I. E., & Charlton, D. (2006). Why experts make errors. 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