A "mess" created by an investigator at a crime scene could lead to another mistaking it for "evidence".
This warning has come in the latest guidelines prepared by the Chandigarh-based Centre for Forensic Sciences Laboratory for investigators involved in the collection, storage and transportation of crime scene biological samples.
Asking investigators to be vigilant while conducting crime scene investigations, the 26-page document outlines the do's and don'ts while one is at the scene of crime which is abundant with clues to solving it.
“The goal of crime scene investigation is to identify, document and collect physical and biological evidence at the scene of crime and must be done with great care and a thoughtful approach since the case under investigation has to be put in the court. Solving the crime depends on piecing together the evidence to form a picture of what happened at the crime scene,” it said.
Crime scene investigation includes securing the crime scene, photography, a proper search of the crime scene, systematic documentation of the crime scene along with the suitable collection, packaging, preservation and transport of all evidence encountered at a specific crime scene, it said.
The guidelines specify that the privacy and confidentiality of scene of crime should be maintained and investigators should "not allow the media" into this space. Control the flow of personnel and animals entering and leaving the scene to maintain the integrity of the crime scene, it added.
"An investigator must be neat and tidy at the scene, as a mess created by an investigator in the crime scene may be mistaken for evidence by another investigator," the guidelines warn.
Allowing media personnel and the public to the crime scene were cited several times, including the Arushi Talwar murder case, as the reasons for investigators' inability to collect valuable evidence.
“In a majority of the cases, the investigating officer who protects and searches a crime scene plays a critical role in determining whether physical evidence will be used in solving or prosecuting crimes,” the guidelines said.
During documentation at the crime scene, it also said, the notes and reports should be done in a chronological order and “should include no opinions, no analysis or no conclusions but just facts”.
A general description of the scene should be given just as the investigator sees it when she does the preliminary survey.