Name _______________________________ Group ___ Date ___________________________________

Introduction to Forensic Science: Crime Scenes

Warm Up Objective: Scientists will describe crime scene analysis by analyzing their mini crime scene.

1. What is the topic?

2. What will you be doing?

3. Why is this important?

4. How will you know if you have done well?

Crime Scenes

Who is on the team in a crime scene investigation? What do they do?

____________________________________: Usually first to arrive. A district attorney may be present to determine whether a search warrant is necessary.

____________________________________: Document the crime scene in detail and collect evidence. Recorders to record the data, sketch artists to sketch the scene, photographers to take photos of the scene, and evidence collectors.

____________________________________: Determine the cause of death ____________________________________: Look for leads by interviewing witnesses and talking to the crime

scene investigators about the evidence ____________________________________: Entomologists---insect biologist, forensic scientists, forensic

psychologist, forensic anthropologists, etc. may be consulted if the evidence requires their expertise.

The Seven S’s of Crime Scene Investigation:

1. ______________________ the Scene: This the responsibility of the first responding police officer (first responder). The _______________of all individuals in the area is the first priority. Preservation of ______________ is the 2 nd priority. Restricts unauthorized persons from entering. Transfer, loss, or contamination of evidence can occur if the area is left unsecured (Locard’s exchange principle). A security log of all those who visit the crime scene will be taken. The officer collects pertinent information and requests any additional needs required for the investigation.

2. ______________________ the Witnesses: Witnesses must _____________ be allowed to talk to each other. Their accounts of the events will be compared. This separation is done to avoid witness working together to create a story (____________________________). The following questions need to be asked of each witness: When did the crime occur? Who called in the crime? Who is the victim? Can the perpetrator be identified? What did you see happen? Where were you when you observed the crime scene?

3. ________________ the Scene: Forensic examiners scan the scene to determine where ____________ should be taken. A determination may be made of a__________________ crime scene and _________________ crime scene.

4. ________________ the Scene: ___________ of the overall area and closeup photos with and without a measuring _________________ should be taken. Triangulation of stationary objects should be including the photos as reference points. A view of the crime scene should be taken from several different ____________ and ____________________. Several close-up photos of any evidence and bodies should be taken.

5. ______________ the Scene: An accurate ____________________ of the crime scene is made, noting the _____________of the body (if any) and any other evidence. All objects should be measured from two immovable landmarks. North should be labeled, and a____________ of distance should be provided. Any other ___________ in the vicinity should be included (doors, windows, furniture, trees, vehicles, hedges, and other structures). Later, a more accurate, final copy of the crime scene should be made for possible presentation in court. Computer programs are available to later create a neater and more accurate sketch suitable for use in court proceedings.

6. ______________________ for Evidence: A _______________ should be walked, and location of evidence marked, photographed, and sketched. Single investigators may use a grid, linear, or spiral pattern. A group of investigators might use a linear, zone, or quadrant pattern. These patterns are ________________________, ensuring no area is left unsearched. Additional light sources might be needed to find hair and fibers. A flashlight for examination and forceps for collecting are preferable, since this method avoids picking up extra materials that are not evidence.

7. ____________________________________________ Evidence: All ___________________ needs to be properly packaged, sealed, and labeled. Specific __________________________________ for evidence collection and storage must be followed. Liquids and arson remains are stored in airtight, unbreakable containers. Moist biological evidence is stored in breathable containers, so the evidence can dry out, reducing the chance of mold contamination. After the evidence is allowed to dry, it is packaged in a paper bindle (druggist’s fold), which can then be placed in a plastic or paper container. This outer container is sealed with tape and labeled with the signature of the collector written across the tape. An ________________________ and a _______________________ document must be attached to the evidence container. The evidence log should contain all pertinent information, including the case number, item inventory number, description of the evidence, name of suspect, name of victim, date and time of recovery, signature of person recovering the evidence, and the signature of any witnesses present during collection. In securing evidence, maintaining the chain of custody is essential. The individual who finds the evidence marks it for identification and bags the evidence in a plastic or paper container. The final container for the evidence is a collection bag, which is labeled with pertinent information. The container is then sealed, and the collector’s signature is written across the sealed edge. The container is given to the next person responsible, who will take it to the lab and sign it over to a technician, who opens the package for examination at a location OTHER than the sealed edge. On the completion of the examination, the technician repackages the evidence with its original packing, reseals the evidence in a new packaging, and signs the chain-of-custody log attached to the packaging. This process ensures that the evidence has been responsibly handled as it was passed from the crime scene to the courtroom.

Step 1: Securing the Scene

Place crime scene tape around your crime scene.

On the lines below, write the names, dates, and times of any person visiting the scene.

______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Step 2: Separating the Witnesses

In this case, there are no witnesses to separate. On the lines below, write the possible interview of a witness for your scene.

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Step 3: Scanning the Scene

Establish forensic examiners. On the lines below, answer these two questions:

1. Where should photos be taken?2. Is this a primary scene? A secondary scene? Explain your response.

__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Step 4: Seeing the Scene

Establish a crime scene photographer.

Take photos of the overall area from various distances and angles.

Create evidence markers. Work with your team to place these evidence markers with evidence. Take closeup photos with and without a measuring ruler.

Step 5: Sketching the Scene

Create a rough sketch of the scene on the next page or a separate paper. Use an appropriate scale. Use labels to identify key objects.

Step 6: Search for evidence

What type of pattern would you use? ______________________ Why would this type of pattern be most appropriate? __________________________________________________________________________________________________

Do NOT actually collect the evidence, but what evidence exists (or probably exists) that would need to be collected? Explain briefly what this evidence might explain about the victim, suspect, or events. ______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Step 7: Securing and Collecting evidence

Do NOT actually collect the evidence. Explain on the lines below how would you collect the evidence present at your scene. Why would you use this method? ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Complete the evidence log for one piece of evidence.

Why is keeping a chain of custody important? ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________