…there is wide variability across forensic science disciplines with regard to techniques, methodologies, reliability, types and numbers of potential errors, research, general acceptability, and published
Understanding the scientific method, as it is applied in forensic science, will help legal professionals make informed decisions about what to allow into court, and what weight should be applied to the evidence by the trier of fact.
How does science underpin the forensic sciences and their disciplines? The answer isn’t a simple one. Many scientific and legal minds have put a lot of time and thought into this matter.
Some analysts follow science methodology to investigate a crime, especially when reconstructing events. Not all scientists agree with this application of the scientific method; they argue that an investigation should not begin with a hypothesis, but rather with an objective gathering of data.
But all analysts agree that many of the disciplines that make up the forensic sciences have the scientific method at their core because they are based on traditional “hard” sciences.
The scientific method uses a very specific set of steps, as explained in the video “The Scientific Method: A Tour” on the right side of this page. Scientists use different variations of the scientific method to solve problems.
Deductive reasoning skills are useful in scientific investigations. Deductive reasoning applies broad principles to predict specific answers. For example, the broad principles of human genetics can be applied to DNA analysis, usually yielding very reliable results.
Inductive reasoning is the counterpart of deductive reasoning. It relies on a series of specific pieces of information to extrapolate a broad conclusion. Forensic scientists might use inductive reasoning to determine where in the house a fire started, or what the bloodstain pattern at a murder scene might reveal. Of course, the physical evidence never depicts all the events that happened in space and time, so inductive reasoning carries a greater level of uncertainty. The inferences and results are based on limited information rather than a more solid scientific principle. But it’s useful in resolving problems where no broad principle can be applied.
Ultimately, it falls to the analyst to identify the best tools and approach for each case.