The proper crime scene techniques

Blood Stains Blood that is in liquid pools should be picked up on a gauze pad or other clean sterile cotton cloth and allowed to air dry thoroughly, at room temperature. It should be refrigerated or frozen as soon as possible and brought to the Laboratory as quickly as possible. Delays beyond 48 hours may make the samples useless. If close to the Laboratory, deliver stained object immediately.

The proper crime scene techniques

Basic Stages for a Crime Scene Investigation — Possible Homicide Don Penven Approach the Scene The crime scene investigator returns the microphone to its clip and begins the drive to the latest assignment.

The proper crime scene techniques

A crime scene investigation begins well before the CSI enters a structure, an open field or wooded area. Usually the radio dispatch message is brief and seldom reveals the full nature of the incident.

Most often this is done to avoid drawing on-lookers and the media who may be monitoring the dispatch frequency. As the CSI turns onto the street in question, his first obligation is to "turn on" his powers of observation.

He may make a mental note of what he sees, hears and smells-or better still-records them on a digital voice recorder. His first reaction to the scene must be, "Does anything look out of place? What odors may be noticeable and are there unusual sounds.

Secure and Protect the Scene Hopefully the first responders haven't caused too much disruption to any potential physical evidence. Before even stepping inside the structure, ingress and egress to it must be controlled. Sentries at all possible entrances should be put in place.

The CSI, after learning the basic facts-in this case it appears that a white male appears to have a single bullet wound the head and rigor has set in-- this from the first responders, so the CSI will establish the boundaries of the crime scene.

Then… out comes the crime scene tape. Initiate Preliminary Survey Again… before entering the structure an exterior survey is needed. This may be nothing more that walking around the exterior of the structure to see if any obvious evidence is apparent. This would include open windows, damaged doors, ladders and the like.

The question the CSI is asking is… how was entry made to the structure? Once indoors, the CSI will make a visual survey of the actual room in which the incident reported took place. This is a good time to also take overall photos of the scene. He will then survey adjoining rooms to determine if these spaces may have information relative to the incident.

Most law enforcement agencies conduct such investigations of an unattended death no physician present as a possible homicide-until it is determined otherwise. Unlike some TV dramas, the CSI is on site for the purpose of finding, evaluating and collecting physical evidence.

Evaluate Physical Evidence Possibilities The very nature of what appears to be obvious should trigger the thought-processes of the CSI. What happened here, when did it happen and what sort of evidence should be present? Questions that should be answered initially are: Did the shooting occur in this room Has the body been moved by first responders or perpetrator s Has any object been moved especially by first responders or family members Were additional shots besides the one in the victim's head.

This means examining walls, ceiling, room objects, etc. Are shell casings apparent. If so-mark them with placards, evidence tents, etc. Are traces of blood apparent in other areas of the room-indicating movement of the victim Is blood spatter apparent Are there signs of a struggle Are there visible footprints in the blood Each crime scene may well generate other questions to be answered by the CSI.

The above list is simply the most obvious questions.

The proper crime scene techniques

Prepare a Narrative of the Scene The CSI's notes can serve as a very critical part of the overall physical evidence available from the scene.Processing a crime scene requires great attention to detail and nuance.

In order to preserve evidence, proper steps must be taken in chronological order. What would happen if the victim were taken to the coroner's office before photographs were taken? Bullet trajectory techniques complement the blood-spatter analysis, and digital photography helps investigators preserve the appearance of the crime scene for future analysis.

Physical Evidence One of the most crucial techniques used by forensic investigators is to analyze physical evidence left at a . Crime Scene Collection Techniques The importance of avoiding cross contamination cannot be overemphasized. The crime scene investigator performing the collection must ensure tools are clean or sterilized and that gloves are changed between handling each sample.

also as an evidence technician, crime scene technician, forensic investigator, criminalist officer, and crime scene analyst, a crime scene investigator has quite their time on the crime scene handling matters such as securing the crime scene, collecting physical evidence, taking photographs, programs will lead you into the area to become a Crime Scene Investigator.

Start studying Crime scene search methods. Learn vocabulary, terms, and more with flashcards, games, and other study tools. It is quite common in crime scene reconstruction for some type of analysis, e.g., trajectory, blood spatter, etc., to be based on measurements taken at a crime scene.

The foundation for the analysis is based on the assumption that adequate and proper scene measurements were obtained. If the methodology is called into question during a legal proceeding, then the resulting analysis could be.

Evidence Collection Guidelines