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Dylan Prather

on 21 February 2014

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HIV/AIDS is a blood born pathogen that is present in some body fluids. It can't be contracted through casual contract such as, swimming pools, door knobs, water fountains, etc. It is typically contracted through shared toothbrushes, razors, mosquitoes, etc.
AIDS purple-colored lesion
There are several diseases that can be contracted during crime scene investigations, lets take a look at a few. This is the most serious disease in the world and is the leading cause of liver cancer. Hepatitis C can be contracted from the mother to her newborn during the delivery process.

Hepatitis B is shown in the picture
-Identify crime scene health issues
-Discuss three broad categories of evidence

-Distinguish between the preliminary and follow-up investigations
-Identify the objection of crime scene investigation
-Explain the importance of crime scene coordination
-Explain the factors that may affect crime scene processing plans

- Explain the "rules" for crime scene investigators
-Understand the skills and qualities needed by investigators
Crime Scene Health Issues
Three broad categories of evidence
There are (3) types of evidence when it comes to a crime scene, they are as follows,

-Corpus Delicti Evidence
At each crime scene the investigator must keep in mind the unique requirements of proof for the case and attempt to locate related evidence.

-Associative Evidence
This helps connect the perpetrator to the scene or victim, or connects the scene or victim to the suspect.

-Tracing Evidence
The identification and location of the suspect are the goals of, tracing evidence

Distinguishing between preliminary and follow up investigation
The preliminary investigation is when the actions taken by the first officer to arrive at the scene of a crime after its detection and/or the reporting of the crime.
The follow up investigation is when, the police effort expended after the initial incident report is completed until the case is ready for prosecution. This step is typically taken from a uniformed officer from the patrol division and consists of the following steps...
1.) Receipt of information, initial response, and officer safety procedures

(A) Note all dispatch information: time, date, type of call, location, name of parties involved etc.
(B) Be alert for people and cars leaving the crime scene or its immediate proximity and note their numbers and descriptions.
(C) Approach the scene cautiously
(D) In assessing the scene, use all your senses: look, listen, smell and be alert!
(E) Determine whether a tactical situation exists, such as a barricaded subject
(F) Remain alert and attentive. Assume that the crime is in progress until you can safely conclude that it is over and the suspects are no longer on the scene.
(G) Make sure that you follow departmental contact protocols. You might need to notify a supervisor in special situations
(H) Treat the location as a crime scene until you conclude otherwise
(I) If the suspect is still at scene, arrest him/her and conduct a legal drugs and weapon/ officer safety search of the person(s)
(J) An officers field notes should also include information about a variety of scene conditions.
2.) Emergency Care

(A) Saving the victims life has a higher value than preserving physical evidence
(B) Asses level of injuries to the victim and request any needed medical assistance, you might need to provide first aid until EMT's arrive.
(C) Point out potential evidence to medical personnel
(D)Obtain as much information as possible from the victim before he/she is moved to the hospital by EMT's
(E) Do not allow EMT's to clean the scene
(F) Get the names of attending medical personnel, as well as their locator information
(G) If there is a chance that the victim may die, attempt to get a dying deceleration

3.) Secure scene and control persons evidence

(A) As rapidly as possible, identify the boundaries of the crime scene and secure it
(B) In defining the scene, officers must make sure that they also identify possible or actual lines of approach to, and flight from, the scene and protect them also.
(C) Maintaining crime scene control is a crucial element in the preliminary investigation
(D) Separate any potential combatants to avoid violence. Make sure that suspects are separated so that they can't "Get their story together" and make sure that witnesses are separated so that they don't contaminate each others recollection.
(E) Set up a physical barrier to protect the scene, prevent the contamination or theft of evidence and for your own safety.
(F) Maintain a crime scene entry log of persons coming and leaving the scene.
4.) Issue a be-on-the-lookout (BOLO)

(A) If the suspect is not arrested issue a BOLO to other officers.
(B) Whenever possible, a (BOLO) should include: number of suspects, age, race, sex, height, weight, build, coloration, birthmarks, tattoos, etc.

5.) Conduct neighborhood and vehicle canvas

-This is an attempt to locate witnesses who may have heard, seen, or smelled something of investigative importance.

6.) Administrative procedures for processing crime scenes

(A)Departments with fewer than 20 officers, typically, a patrol officer will also be the detective. It is important that he/she note all key facts.
(B) Chain of custody is a must in crime scene investigation. This is the sheet for who had the evidence and when. There must be NO errors in this process of the case or all charges could be dismissed.
(C) In larger agencies, typically a crime scene tech will will process the evidence.

7.) The incident/ Offense Report

-This is typically the arriving officers field notes and what the officer observed when he/she arrived at the scene. Typically, a supervisor reviews and approves the incident report.

The preliminary investigation consists of the first officer on scene after its detection or after reported to Law Enforcement
Identify the objection of crime scene investigation
(Part 2)

The objection of crime scene investigation is to legally collect and obtain evidence that will bring a successful prosecution to the suspect and bring justice to the victim and his/her family.

Explaining the importance of crime scene coordination
The coordination/organization of a crime scene is very important, in fact it's essential that it's done right, for a successful prosecution. Once a criminal offense has been committed, there are (3) possible outcomes. First, it could go undetected. For example, an organized murder in which the body is maliciously cut up and thrown in a river. Secondly, be detected but not reported. For example, the victim might not like contact with the police, so they avoid contacting authorities. Finally, come to the attention of police, through observation, a complaint by the victim or witness, or a tip. A crime has occurred in all (3) scenarios. But, only the last one is of concern to the investigator, because then a formal process may begin. Refer to the diagram on the next slide for the formal process...
Crime reported or detected by police
Preliminary Investigation
Immediate vicinity search
On-scene arrest
Warm search
Immediate- vicinity arrest
Follow-up investigation
No arrest
Explain the factors that may effect crime scene processing plans
The Senior criminal investigator assigned to this case, will typically have the responsibility for what happens at the crime scene. Typically, he/she will conduct a "walk through" of the scene and develop a "plan" for the investigation. One of the most crucial roles is typically coordination. Depending on the capacity of the crime, typically a "headquarters" or "mobile CSI" headquarters will be stationed near the scene. This will be the "Meet up" point for investigators. It's also very important that you have someone with a "log", logging who goes in and out of the scene, and what their purpose is.
Some factors that may effect crime scene processing plans include, the fact that a crime scene processing unit can not be called out to every crime scene, and sometimes patrol officers will need to process the crime scene. When you are processing the scene make sure that you follow ALL department protocols, and that you notify a supervisor pertaining to the crime scene you are on. As Police officers, you'll more than likely want to "stop by and help" at a large crime scene, when in reality, you are just curious, and it often times make thing more confusing and stressful for investigators. It's best to stay away from the scene if you are not needed.

Explaining the "rules" for crime scene investigators
The number one "rule" that the crime scene investigator must understand is that maintaining control is essential. Without control at a crime scene, a life could be lost, evidence destroyed, assignments overlooked, or the investigation conducted in a generally haphazard manner. At the scene of sensational crimes such as robberies, homicides, or those involving well known victims, the media will respond within minutes to begin videotaping bystanders, victims, investigators etc. It's best to let your Public Information Officer handle these, or the officer in charge of the crime scene. You should cooperate with the press, but be sure that you protect the legal rights of the suspect, avoid placing a witness in danger or damage the integrity of the case. Another "rule" that the crime scene officer should follow is that they should conceptualize events. You shouldn't walk into a house where a dead body is, and a gun in their hand, and automatically rule it a suicide. Look at all the evidence and where it leads you. The, "Funnel Theory", is an example where you throw all of the possible causes of the crime into a "drawn funnel", look at your evidence, and see where it takes you. Don't rule things out to quickly, and be thorough in your investigation. Also, investigators should follow the "rule" stating, proceed with caution. NEVER move any of the evidence at a crime scene unless it is an officer safety issue. By moving things, you could be destroying evidence. Another "rule" that the investigator must make is that they should apply inclusiveness, this simple, but confusing, rule states that every available piece of evidence be obtained, and where there is question as to whether a particular item constitutes evidence be defined as such. The final "rule" that should be followed by investigators is that maintaining documentation is crucial. 7 key documents must be at a crime scene. They are, crime scene entry log, this tells you who went in and out of a crime scene. Administrative log, this is kept by the officer in charge, and shows everyone what their responsibilities/ duties are at the scene. Assignment sheet, this is to be completed by every officer with a duty and the results of what they were assigned to do, both positive and negative. Offense report, is to be done by the first officer at the scene. Photographic logs, this tells you who took what picture, where at, what conditions, and some of the circumstances. A rough sketch of the crime scene, is typically done by your crime scene tech. And, finally, evidence recovery log. This lists out the items, who collected it, location, date and time. Refer to the next slide to see examples of each.
Understanding skills and qualities needed by investigators
Categories of evidence
There are 14 essential qualities that the investigator should have, they are...
1.) Have self-discipline
2.)Use legally approved methods and have high ethical standards
3.) Have the ability to win the confidence of people with whom they'll interact with
4.) Do not act out on malice or bias
5.) Include in their case documentation all evidence that may point to the innocence of the suspect, no matter how unsavory his or her character
6.) Know that it's more of a science than an art
7.) You'll often times have to use your own resourcefulness to solve investigations
8.) Have wide-ranging contacts across many occupations
9.) Are not reluctant to contact experts from many different fields to help move the investigation forward
10.) Use both inductive and deductive reasoning
11.) Know that the inductive and deductive reasoning can be distorted
12.) Learn something from everyone in which you come in contact with
13.) Have empathy, sensitivity, and compassion without causing unnecessary anguish. Ex: When interviewing a rape suspect
14.) Avoid becoming cynical from constant contact with criminals
Now you should be able to understand a few of the crime scene health issues that investigators face. You should also be able to determine and explain the three broad categories of evidence. Also, be sure that you know the difference in a preliminary investigation and a follow up investigation. Make sure that you are aware of the crime scene objectives, and that you follow them closely. You should also be able to explain to someone why crime scene coordination is so important. When seeking an investigator make sure that they have the qualities as described. Make sure that you follow all of the "rules" when doing an investigation. And lastly, be certain that you can explain factors that may effect crime scene processing plans
This is an example of the funnel theory. Throw all of the ideas into a funnel and the let evidence lead you.
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