Take out your notes – we are going to Take out your notes – we are going to lecture on Ch. 2.lecture on Ch. 2.

Be sure to turn in your Ch. 2 HW!Be sure to turn in your Ch. 2 HW!

While you are waiting, respond to While you are waiting, respond to the following:the following:

1.1.What is What is physical evidencephysical evidence??

2.2.When police are called to a crime When police are called to a crime scene, what are the first few things they scene, what are the first few things they should do?should do?

Tues, 9/30Tues, 9/30

Ch. 2 The Crime SceneCh. 2 The Crime Scene

CHE 113 3

Processing the Crime SceneProcessing the Crime Scene

1.1. 11stst officer on the scene officer on the scene

2.2. Surveying the crime sceneSurveying the crime scene

3.3. Documenting the crime sceneDocumenting the crime scene

4.4. Searching the crime sceneSearching the crime scene

5.5. Collecting physical evidenceCollecting physical evidence

CHE 113 4

1. First officer on the scene1. First officer on the scene

1.1. Check for immediate safety concernsCheck for immediate safety concerns

2.2. Assist the victimAssist the victim

3.3. Search for/arrest suspectSearch for/arrest suspect

4.4. Detain and separate witnessesDetain and separate witnesses

5.5. Protect the crime scene (barrier tape)Protect the crime scene (barrier tape) Limit entry to scene to necessary personnelLimit entry to scene to necessary personnel

6.6. Note any changes made to the sceneNote any changes made to the scene

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2. Crime scene survey2. Crime scene surveyThings to consider when defining the crime scene:Things to consider when defining the crime scene:

Location of Criminal ActivityLocation of Criminal Activity Primary crime scene: Primary crime scene: Where the original crime occurredWhere the original crime occurred Secondary crime sceneSecondary crime scene: Subsequent crime scenes: Subsequent crime scenes

Example: Where body was dumpedExample: Where body was dumped

Size of AreaSize of Area Type of Crime CommittedType of Crime Committed

Robbery, homicide, sexual assault. Etc.Robbery, homicide, sexual assault. Etc. Physical Location of the CrimePhysical Location of the Crime

Indoors/outdoors, apartment, vehicle. Etc.Indoors/outdoors, apartment, vehicle. Etc.

CHE 113 6

The Preliminary ExamThe Preliminary Exam A A lead investigator lead investigator will start the process of will start the process of

evaluating the area. evaluating the area. First, the boundaries of the scene must be First, the boundaries of the scene must be

determineddetermined Followed by the establishment of the Followed by the establishment of the

perpetratorperpetrator’’s path of entry and exit.s path of entry and exit. The investigator then proceeds with an initial The investigator then proceeds with an initial

walk-through of the scene to gain an overview walk-through of the scene to gain an overview of the situation and develop a strategy for the of the situation and develop a strategy for the systematic examination and documentation of systematic examination and documentation of the entire crime scene.the entire crime scene.

Search pattern determinedSearch pattern determined This is done before processing the crime scene for This is done before processing the crime scene for

physical evidence.physical evidence.

CHE 113 7

Information Gathered From the Information Gathered From the Crime SceneCrime Scene

Corpus DelictiCorpus Delicti: : the body of the the body of the offenseoffense Must prove a crime has been Must prove a crime has been

committed committed Ex: dead body should be found in Ex: dead body should be found in

murder trialmurder trial Modus Operandi (MO)Modus Operandi (MO):: a certain a certain

criminal’s repeated behaviorcriminal’s repeated behavior Linkages of persons, places, and thingsLinkages of persons, places, and things Prove or disprove witness statementsProve or disprove witness statements Identification of potential suspectsIdentification of potential suspects Provide investigative leadsProvide investigative leads

CHE 113 8

3. Documenting the crime scene3. Documenting the crime scene CSIs only have a short time to work with the CSIs only have a short time to work with the

scene in an untouched statescene in an untouched state Notes, photographs, and sketches (sometimes Notes, photographs, and sketches (sometimes

video) are taken at every crime scenevideo) are taken at every crime scene Note taking must be a constant activity Note taking must be a constant activity

throughout the processing of the crime scene. throughout the processing of the crime scene. Notes must include:Notes must include:

Detailed description of the scene with the location Detailed description of the scene with the location of items of physical evidence recovered. of items of physical evidence recovered.

For each piece of evidence discovered:For each piece of evidence discovered: Time it was foundTime it was found Who found itWho found it Notes on its condition when foundNotes on its condition when found How and by whom it was packaged and markedHow and by whom it was packaged and marked The disposition of the item after it was collectedThe disposition of the item after it was collected

CHE 113 9

Personnel Duties and Personnel Duties and ResponsibilitiesResponsibilities

Photographer and Photographic Photographer and Photographic Log RecorderLog Recorder Photograph entire scene (before and after Photograph entire scene (before and after

entered)entered) Photograph victim, crowd, vehiclesPhotograph victim, crowd, vehicles Photograph evidence before itPhotograph evidence before it’’s moved s moved

(including fingerprints, casts, etc.)(including fingerprints, casts, etc.) Photograph evidence both in wide view (position Photograph evidence both in wide view (position

at scene) and close-up (with scale)at scene) and close-up (with scale) Possible use of video recording (does not Possible use of video recording (does not

replace still photographyreplace still photography Prepare photographic logPrepare photographic log

CHE 113 10

Capture Crime SceneCapture Crime Scene

CHE 113 11

Wide angle lenses are used to Wide angle lenses are used to distort the truth or emphasize itdistort the truth or emphasize it

CHE 113 12

Details preservedDetails preserved

CHE 113 13

Personnel Duties and Personnel Duties and ResponsibilitiesResponsibilities

Sketch Preparer Sketch Preparer Diagram area of scene (incl. orientation)Diagram area of scene (incl. orientation)

Rough sketch – reasonably accurate Rough sketch – reasonably accurate dimensions, orientation and location of dimensions, orientation and location of evidence (from a fixed point)evidence (from a fixed point)

Finished sketch - aesthetic appearance, Finished sketch - aesthetic appearance, drawn to scale (usually done later sometime drawn to scale (usually done later sometime w/ CAD)w/ CAD)

Set forth major items of evidence on Set forth major items of evidence on sketch (with scale)sketch (with scale)

Make measurements (double check)Make measurements (double check)

CHE 113 14

Sketch Preparer Sketch Preparer

Rough Sketches

CHE 113 15

Sketch Preparer Sketch Preparer

Finished Sketches

CHE 113 16

Sketch Preparer Sketch Preparer

CHE 113 17

Creating A Finished SketchCreating A Finished Sketch

Read instructions as a classRead instructions as a class Discuss differences between a rough Discuss differences between a rough

and a finished sketchand a finished sketch Time to work (you will have Time to work (you will have

tomorrow as well)tomorrow as well) Leave your work thus far in the in Leave your work thus far in the in

folder unless you are sure you won’t folder unless you are sure you won’t lose it!lose it!