Determining the Dimensions of the Homicide Crime Scene

This section focuses on the crucial steps in identifying and securing the crime scene perimeter. The cardinal rule emphasized is to protect and preserve the crime scene. The process involves verifying the victim's death, finding physical evidence, and taping off the crime scene boundaries.

The text provides guidance on how to determine the boundaries of a crime scene, emphasizing the importance of clearing the largest area possible and considering factors such as location, presence of evidence, eyewitness statements, and natural boundaries.

Highlight: When possible, maintain an outer perimeter around a crime scene of at least the largest area that can be reasonably secured.

The chapter also addresses the importance of protecting the crime scene from unauthorized access and lists potential areas that should not be overlooked, such as points of forced entry, routes of escape, and the suspect's clothing and body.

Example: Areas to protect in a complex crime may include the suspect's residence, the location from which the body was moved, and the vehicle used in the crime.

Protecting the Crime Scene

This section delves into the critical aspects of crime scene security and preservation. It emphasizes the importance of keeping unauthorized people out of the crime scene, acknowledging that the difficulty of this task can vary depending on the location.

The text provides a comprehensive list of methods to secure a crime scene, including:

• Rope
• Barricades
• Police vehicles
• Additional officers
• Volunteers (as a last resort)
• Crime scene cards
• Reflective crime scene ribbon

Highlight: The presence of officers adds to the effectiveness of crime scene security measures.

The chapter also identifies basic scene contaminators, such as weather, relatives or friends of the victim, suspects and their associates, curious onlookers, and even other officers or high-ranking officials.

Vocabulary: Scene contaminators are factors or individuals that can compromise the integrity of a crime scene.

The Crime Scene Sign-in Sheet and Preliminary Investigation

This section introduces the concept of a crime scene sign-in sheet as an effective tool for securing the crime scene and preserving evidence. It explains that the purpose of this measure is to stop unauthorized personnel from entering the scene.

The text suggests establishing two crime scenes as a solution to potential issues:

1. Primary - the real scene
2. Secondary - a secure area to allow people to feel involved without compromising the actual crime scene

The chapter then outlines the steps of the preliminary investigation at the primary crime scene, which includes:

1. Investigator walkthrough
2. Gathering information from responding officers
3. Verifying the condition of the victim
4. Ensuring the primary crime scene is intact

Highlight: The walk-through allows investigators to get a feel for what happened and establish crucial consistencies and inconsistencies that will guide the direction of the investigation.

Example: During the preliminary investigation, investigators may identify additional areas that need protection or evidence that needs to be collected.

The text concludes by emphasizing that the most important aspect of the primary crime scene is the presentation of the body, as it provides crucial information for the investigation.

Quote: "If anything can go wrong, it will be at the crime scene."

Specialized Investigation Scenarios

This portion addresses complex investigation scenarios and common pitfalls in homicide investigation.

Definition: Equivocal death investigations involve cases where facts may be purposely vague or misleading.

The chapter details important aspects of thorough investigation:

• Examination of victim's personal effects
• Analysis of electronic devices
• Review of physical recordings
• Neighborhood canvassing

Highlight: Staged crime scenes require particular attention to detail and skepticism from investigators.

Chapter 1: The Homicide Crime Scene

The chapter begins by emphasizing the critical nature of homicide crime scenes and the basic principles involved in initiating an effective homicide investigation. It outlines the five components of Practical Homicide Investigation: teamwork, documentation, preservation, common sense, and flexibility.

The text explains that the primary crime scene is where the body is found, which may differ from where the murder occurred. It stresses the importance of focusing resources on this location and clarifies that there are no secondary crime scenes, only multiple crime scenes.

Definition: Corpus delicti refers to the body of evidence that proves a crime has been committed.

Highlight: The crime scene is proof that a crime has been committed and contains all corpus delicti.

Example: Multiple crime scenes may include where the body was moved from, where the assault leading to death took place, or where evidence connected to the crime was discovered.

The chapter also introduces Locard's theory of transfer, which explains the exchange of trace evidence between the perpetrator, victim, and crime scene.

Vocabulary: Res gestae refers to "things done," including spontaneous statements made by a suspect.