1. Forensics Chapter 3 THE CRIME SCENE

2. AT THE CRIME SCENE Crime scene: any place where evidence may be located to help explain events. ALL crime scenes must be treated carefully or evidence can and will be lost. Evidence that is not collected/has been tampered with can lead investigators in the wrong direction; which can possibly convict the wrong person of a crime. Information must be gathered that allows investigators to reconstruct the sequence of events, the modus operandi, and the motive for the crime. modus operandi: the characteristic method of operation of a criminal; also known an “MO” The purpose of carefully analyzing the crime scene is: To learn what happened, To gather evidence, To convict the person responsible for the crime.

3. AT THE CRIME SCENE A crime scene investigator MUST BE: Experienced Knowledgeable Capable of deciding which evidence is important and which is unimportant What happens when there is an error made in the investigation process? Can it be correct? How? Can crime scenes be in more than one place? If so, how can this be? There are important steps that MUST BE followed when conducting an investigation.

4. PRESERVING AND ISOLATING THE CRIME SCENE What is the role of the first officer at the scene of a crime? Attend anyone who needs medical attention (if needed) Make an arrest (if needed) Protect the scene! No unauthorized persons shall enter the scene. Witnesses and suspects must be detained If there has been a death, the medical examiner must be called. Then… Body must be noted of condition Estimate the time of death (if possible) Collect any physical evidence surrounding the body

5. AT THE CRIME SCENE The Investigator must interview _____ to learn what happened. The first responder Victim Witness(es) Law enforcement officers should: Note and record details such as: weather conditions particular odors whether lights were on or off any signs of prior activity at the scene light visibility

6. OBSERVING AND DOCUMENTING THE SCENE Investigators should examine the crime scene to get an overall view picture through: Possible items of evidence Points of entry and exit Possible consideration of what happened Mentally outlining how the scene should be handled when collecting the evidence How do investigators get this important information? Observation and detailed notes

7. Methods of documentation: Notes Photography Sketches Video OBSERVING AND DOCUMENTING THE SCENE

8. NOTES Note taking is one of the most important parts of processing the crime scene. Investigators MUST be observant because they must remember every detail! Notes should be complete and thorough, written clearly and legibly. Measurements are EXTREMELY important and must be referred to in describing the evidence.

9. NOTES Notes should include: Date and time Description of location, weather, and environmental conditions Description of crime Location of evidence relative to other key points Names of all people involved, including authorized personnel, witnesses and victims All changes that have occurred and other relevant information

10. NOTES When noting physical evidence, it is important to note… Location Time of discovery Packaging An investigator may also use a tape-recorder for descriptions, but they must be transcribed later and added to the notes.

11. PHOTOGRAPHS AND VIDEOTAPE “A picture is worth a thousand words” Photos capture details that even the most observant investigator may miss and helps judge/jury visualize the scene. BEFORE TOUCHING ANYTHING!!!!. an investigator must take pictures of the entire crime scene. Special attention is brought to points of entry and exit Photographs should include: Clarification of the scene Close-up of evidence the scene through the eyes of a witness Location of the scene and its surroundings

12. Several photos of evidence should be taken; each from a different angle. A ruler should be in every photograph for reference of scale. Photographs are EVIDENCE and should be treated as such! Videotaping is becoming more prominent in this day in age. When videotaping, an investigator must narrate as they walk through a crime scene. The tape should start outdoors and move indoors to give an external setting. Videotapes are EVIDENCE and should be treated at such! So…is it okay to edit or erase video? Why or why not? PHOTOGRAPHS AND VIDEOTAPE

13. SKETCHES Investigators must take photographs AND sketch the scene. Sketches allow for perspective, help investigators remember details about a crime scene, and give an overall layout with point(s) of entry. Most important roles of sketches is to give… Measurements Scale Relative placement

14. SKETCHES All sketches should include… Date and time Scale Reference points Distance measurements Names of investigators, victims, and suspects Legend

15. SEARCHING THE SCENE FOR EVIDENCE Searching a scene must be methodical and thorough when searching for physical evidence. MOST IMPORTANT PHASE OF AN INVESTIGATION! Investigators look for things that don’t belong. Anything that could possibly carry trace evidence is collected and saved for later examination. What things could possibly carry trace evidence? How could a forensic scientist make “invisible” evidence appear?

16. How the investigator carries out the search depends on… Location Size of the area Complexity of the crime scene Number of investigators matters!! Why? For larger crime scenes, the area may be divided into grids and “swept” in a certain way. SEARCHING THE SCENE FOR EVIDENCE

17. COLLECTING AND PACKAGING EVIDENCE After searching the scene, next the investigator must collect and package the evidence. Everything must be packaged separately and labeled. Why is separation and labeling an important step? Fragile items are packaged FIRST! Fragile items are… Fingerprints Bloodstains Other trace evidence Larger items with trace evidence are collected in whole. Why do you think this is?

18. COLLECTING AND PACKAGING EVIDENCE Good containers for packaging evidence: Pill bottles Vials Manila envelopes Plastic bags Please list the special considerations for some types of evidence.

19. COLLECTING AND PACKAGING EVIDENCE Controls may be collected to compare with any evidence from the crime scene whose source is unknown. The investigator should properly package all evidence and controls, sealing the items with tamper-proof tape and labeling each. Why is this care of evidence so important? Give me a few (3-5) reasons.

20. MAINTAINING THE CHAIN OF CUSTODY There MUST BE written record of who has had possession of the evidence at all times. This is called chain of custody: written record of all people who have had possession of an item of evidence. QUESTIONS! Why is this important? Think of when evidence is brought to trial. Whose names should be on an evidence label? What happens to evidence after it leaves the crime scene?