Scientific Method
Forensic scientists report their findings, or conclusions, to law enforcement and the Court. In their reports, they include observations, data analysis, their hypotheses, tests and procedures, as well as summaries and findings of fact. Findings are scientific conclusions and can be supported by experimental data
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The scientific method involves a cyclical process of hypothesis-> experimentation-> results-> revised hypothesis. Forensic science is similar in nature. An investigation of a crime scene begins with collection of data – observations, measurements, and descriptions. Afterwards, investigators develop one or several possible hypotheses that can be tested using the forensic data and other evidence. The forensic data are used to support, refine, or refute the hypothesis. If a hypothesis is refined, the investigation continues with observations followed by results and analysis. Forensic scientists must look for evidence that might refute their hypothesis of a crime while also looking for confirmatory evidence so that they do not overlook key insights and can assure that the investigation is complete and a criminal conviction is proper.
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It is vital that forensic scientists carefully and systematically label all evidence they come across in their process of collecting data. There is no room for mistaking or losing evidence in high-consequence cases and trials. Forensic scientists must be meticulous in their work so as to prevent inaccurate conclusions.
Pseudoscience in Forensics
Good forensic scientists only report to juries on what they know. They use language such as “this evidence is consistent with…” as opposed to “this evidence proves…”. For example, forensic scientists can conclude that gunpowder molecules are present on a suspect’s hand, but they may not have the evidence to conclude that the suspect actually fired the gun. Similarly, scientists may be able to state that hairs found at a scene look similar to the suspect’s hair, but they cannot be certain that they are definitely from the suspect’s head. Forensic scientists must keep their analysis limited to facts that can be proven in order to avoid pseudoscience.
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