Disturbed evidence
Disturbed evidence refers to materials at a crime scene that have been altered, moved, or destroyed after a crime has taken place. The integrity of a crime scene is crucial for effective investigation, as undisturbed evidence provides the most reliable information to support legal proceedings. When evidence is disturbed, it can compromise the truth of the events that transpired, making it challenging to establish facts in a court of law. Various factors can lead to the disturbance of evidence, including the presence of first responders, natural elements, and improper investigative techniques. Digital evidence also plays a significant role and can be contaminated, necessitating careful handling by forensic experts. Investigators implement strategies such as securing the crime scene, using systematic search patterns, and following a proper sequence for evidence collection to minimize the risk of disturbance. Despite efforts to preserve evidence, disturbances can still occur, and investigators must document any reasonable explanations for these occurrences to ensure the admissibility of relevant evidence in court. Understanding the implications of disturbed evidence is essential for appreciating the complexities of crime scene investigations and the pursuit of justice.
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Subject Terms
Disturbed evidence
DEFINITION: Materials that have been altered, moved, or destroyed at the scene of a crime after the crime has occurred.
SIGNIFICANCE: An undisturbed crime scene yields the most reliable physical evidence to support the investigative process. When evidence is disturbed, the truth of what happened at the crime scene may be compromised or impossible to determine, and may be impossible to prove in a court of law.
The objective of crime scene investigation is to gather that supports or refutes theories surrounding the crime. Toward this end, investigators carefully choose and employ procedures that will maximize the likelihood of the discovery of pertinent evidence and minimize actions that could disturb that evidence. Taking into account Locard’s exchange principle (which states that every contact of an individual with another person, place, or object results in an exchange of materials), it is implausible that all evidence at a crime scene will remain undisturbed throughout the duration of the investigation.
Although investigators may make every effort to maintain evidence in an undisturbed state, it is not unusual for evidence to be disturbed in many different ways. Frequently, evidence is disturbed in the period between discovery of the crime and securing of the scene, when numerous individuals may be present. Evidence such as blood trails, footprints, fingerprints, and pertinent biological fluids may be smeared or inadvertently erased by first responders, and materials not pertinent to the crime (such as fibers from blankets) may be introduced to the scene. Moving a living person or a dead body from the scene without taking precautionary steps to preserve surrounding evidence may result in disturbed evidence.
In the modern era, digital evidence plays an important role in many criminal cases. Like physical evidence, digital evidence can be disturbed or contaminated in ways that make it less useful in a criminal trial. For this reason, digital forensics experts interacting with potential digital evidence must be careful to avoid any inadvertent data mismanagement.
Physical evidence may be disturbed when individuals at the scene move objects, break objects, spill liquids, wipe up spills, remove clothing, cover victims, or otherwise introduce materials onto the scene that are not pertinent to the crime. Natural occurrences can also disturb evidence, such as when a crime victim dies in an outdoor setting and is exposed to weather conditions that alter or wash away materials. Evidence may also be disturbed by inappropriate or careless investigative techniques, such as when a technician pours material into a depression on a surface before checking the surface for fingerprints.
Investigators minimize or prevent the disturbance of evidence by securing the crime scene, by choosing an appropriate crime scene search pattern, and by following an effective sequence of evidence collection. Securing the crime scene entails controlling who is allowed onto the crime scene, designating the entrance and exit paths for responders administering to any victims, and establishing the search methods that will be used. An appropriate crime scene search pattern guides a methodical search that maximizes evidence discovery efforts while minimizing disturbance of the scene. In an effective sequence of evidence collection, pertinent materials are gathered before other investigative actions are taken that could disturb those materials. Through these actions and methods, investigators attempt to ensure that crime scene evidence is not disturbed; when these methods are followed and evidence is nevertheless somehow disturbed, investigators make note of any reasonable explanation for the disturbance so that it does not jeopardize the utilization of pertinent evidence in a court of law.
Bibliography
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