Crime Scene Investigation

• There must be a plan for systematically searching the site that ensures that no stone will be left unturned without needlessly covering the same area again and again
• Safety of the scene searchers must be considered.
• Only highly qualified, trained personnel should conduct the search of the site.
• Contamination must be minimized by permitting as few people as possible access to the site.
• Time may be of the essence.
• The crime scene must be documented throughly so that a record can be made of its condition when the crime occurred.This includes labeling the location of each piece of evidence when it is discovered
• There must be a chain of custody for each piece of evidence that is removed from the scene. The chain of custody begins when the evidence is discovered.

Ascertain if the perpetrator is still at the crime scene. If so, a hot search for the perpetrator should be commence immediately. If not, a cold search should be done. This is where people in the neighborhood are interviewed to determine if they saw the crime being committed, if they may have seen the perpetrator flee the scene, or if theyobserved other suspicious events. Tend to the injured.
	3. Secure the scene 4. Do not walk through the scene and search for evidence 5. Note any obvious safety hazards.

Crime Scene Investigation

One of the first decisions to be made is the search pattern that will be used at the crime scene. This depends on the type of crime. If the scene includes several rooms, each one is searched systematically. If the scene is outdoors in a large area, it may be necessary to divide the scene into grids and then search each grid.

There are two basic methods of documenting a crime scene and recording its condition and the location of all the evidence. The first was by making a freehand sketch and then taking measurements of the positions of various objects with reference to a point. Later, this sketch would be translated into a scale drawing of the scene.The second method was by still photography using regular 35 mm film. Many pictures would be taken under various light conditions and at various distances and angles in hope that some would properly record the scene.

Next is the collecting, preservation, and packaging of evidence . This is a very crucial step in investigating crime scenes. Under ideal circumstances, crime scene investigation would be done by the forensic scientists who analyze the evidence because they know best how to recognize it, collect it, preserve it, and package it. There are three major steps in the process of evidence collection which are recognition, collection, and packaging/preservation.After evidence is collected, it must be packaged or preserved correctly. There must be a record of who is in possession of the evidence form the time it is collected from the scene until the time it gets to court. This is called the Chain of Custody. The evidence must be packaged in tamper-evident packaging. This is both to document and a process that insure the integrity of the evidence.

Once the evidence has been collected and analyzed and compared to known evidence, then the criminal investigators, often with the help of forensic scientists, will attempt to reconstruct the crime, including the identities of the victim(s) and the perpetrator(s) and the sequence of events that took place leading up to the crime. The focus here is to link the suspect(s) to the crime through the evidence and build a case that will stand up in court and that will convince a judge or jury of the guilt of the suspect beyond any reasonable doubt.