Scene of the crime investigation is the assembly point of logic, law and science. Processing scene of the crime is a tiresome and long procedure which entails documentation purposely of the situations in the scene and gathering of physical evidences that will probably shed light on what occurred and will point who did the crime.
At any scene of the crime, a crime investigator may gather a piece of dried blood in a windowpane, by not allowing his arm touch the glass if ever there are some unseen fingerprints there, pick up hair from the jacket of the victim with the use of tweezers but not disturbing the clothes enough in shaking off some white powder (which might be cocaine or not) in the crumple of the sleeves and make use of sled hammer in breaking through the wall which looks as if it is the source of an awful smell.
The physical proof itself is just a component of the investigation. The final objective is the strong belief of the person responsible for the crime committed. Therefore, while the crime investigator scratches off dried piece of blood without staining some prints, picks up many hairs by not disturbing some traces of proof and smashing through a partition in the room, he thinks about all needed procedure to preserve all evidences in their present forms. The crime laboratory will does something about the evidences to restructure the crime or recognize the perpetrator or criminal and the lawful matters involved in ensuring that the evidences are permissible in the court.
The scene of the crime investigation starts when the crime investigation unit accepts a call coming from police authorities or detectives on the crime scene. On reaching the crime scene, the investigator makes sure that the place is secure. Then he/she does a primary walk-through in order to get the entire feel of the scene of the crime, see for himself/herself if anybody has moved or touched anything his/her arrival and then he/she makes initial theory out of the visual assessment. Then he/she notes down some potential evidences. At this instance, he/she do not touch anything.
The crime investigator documents carefully the scene of the crime by taking pictures and make sketches during the second or succeeding walk-through. Occasionally, the documentation period composes a film walk-through also. The investigator documents crime scene entirely and records anything he/she determined as evidence. Up to this moment, the investigator does not touch anything.
After documentation, the investigator systematically and very carefully walks through the crime scene and collects all important evidences, tagging them, logging and packaging them so that they will remain intact in going to the crime laboratory. The crime laboratory then processes all the evidences collected by the crime investigator of the scene. After the laboratory results are ready, they precede to head detective of the case.
Each scene of the crime investigation unit holds the sections among work in the field and laboratory work in different ways. Crime scene analysis or scene of the crime investigation goes on into the crime scene and whatever goes on into the section of the laboratory is known as forensic science. Since not all crime investigators are forensic scientists, they should possess an excellent understanding about forensic science to be familiar with the particular value of several types of evidences while working in the fields. Scene of the crime investigation is a very big undertaking so it is necessary that the crime investigator must possess the qualifications required for the position.