Abstract
Finding and correctly interpreting blood traces can be of utmost importance in solving the circumstances surrounding the perpetration of the crime, the actions of the victim and the perpetrator at the scene, their contribution to the perpetration of the crime, their behavior after the perpetration of the crime. Unless the perpetrator is not known in the first stages of criminal investigation, blood traces, together with other material traces at the scene, can be a significant controlling factor in assessing the credibility and truthfulness of the statements of the event participants. In criminal and judicial practice, cases have been reported in which a thorough qualitative and quantitative analysis of traces of the blood was crucial for identifying the perpetrators, participants, as well as proving their role in the perpetration of the crime.

Introduction
The first few minutes of a crime scene's processing can be the most critical moments of an entire investigation. At no other period will the investigators be closer to the moment the crime was committed. Investigators will never have the area more pristine or more unfettered from contamination. In those first few minutes, fingerprints, shoe prints, tire prints, trace evidence, and the state of the victim are all at their most informative. And yet, at no other time are mistakes more likely made that can potentially jeopardize successful prosecution of the crime's perpetrator.

Crime scene processing is an inherent task and duty associated with most criminal investigations, for rarely does one encounter a crime without some kind of crime scene. Crime scene processing consists of an examination and evaluation of the scene for the express purpose of recovering physical evidence and documenting the scene's condition in situ, or as found. To accomplish this, the crime scene technician engages in six basic steps: assessing, observing, documenting, searching, collecting, and analyzing. These steps, and the order in which they are accomplished, are neither arbitrary nor random. Each serves an underlying purpose in capturing scene context and recovering evidence without degrading the value of either. Any way you look at it, this is not an easy task, since the mere act of processing the scene disturbs the scene and evidence. From these efforts however, the investigator will walk away with important items of physical evidence and scene documentation in the form of sketches, photographs, notes, and reports. All of this information plays a significant role in resolving crime by providing objective data on which the investigating team can test investigative theories, corroborate or refute testimonial evidence, and ultimately demonstrate to the court the conditions and circumstances defined by the scene. This is a task that is easily said, but it is not so easily done.

Action without purpose is folly and, simply put, becomes wasted effort. This is true in any endeavor, so it is imperative that before pursuing the actions an investigator conducts in the crime scene, the investigator must understand his or her mandate. Crime scene processing is a duty in every sense of the word. Crime scene processing is not something the technicians do because "they were told to," but rather because they have a responsibility to do so. If the investigator fails to recognize this duty and its ultimate purpose, many of the procedures used at the scene might appear meaningless and therefore unnecessary.

Blood
Saliva is sprayed, hair is yanked from its roots, skin is scraped off, and flesh is torn. Violent crime inevitably leaves a number of different types of biological materials behind as witness to the attack. With the possible exception of semen in the case of sexual assault, no type of biological fluid or tissue is consistently more revealing about the victim, the attacker, and the circumstances of the assault than blood. Blood can yield DNA that identifies the crime's participants. Its splash patterns can reveal the site and mode of the attack. Blood can make an attacker's fingerprints or shoeprints readily visible.

We can all recognize a bloodstain. If it's fresh, it's red. Older bloodstains are a reddish brown. But not all stains having the color of blood are blood. A

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Blood in Murder Investigation Copyright: © 2019 by Sinisa Franjic. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Based on a work at: Journal of Law and Judicial System, 2(3), 2019, pp. 18-22.

• Collection and Preservation of Blood Evidence from Crime Scenes, by George Schiro
• Listing of 47 bloodstain articles, Crime Scene Investigator Network