Point-to-Point (Link) Search Method: Procedure With Examples

Point-to-point pattern searching focuses on following a trail of evidence or successively connecting evidence within the crime scene. It is also called the Link Search Pattern Method.

It often begins with a critical piece of evidence and expands the search based on the relationships between discovered items.

This technique helps establish walking paths throughout the crime scene to minimize loss and destruction of evidence in unsearched areas (using other crime scene search methods).

When to Use Link or Point-to-Point Searches?

• This method is suitable for crime scenes with multiple points of interest and a need to establish clear paths for investigators to follow.
• Examples such as residential settings with multiple rooms and objects of interest. 

How to Process Area with Link Search Method? (Procedure)

1. First, identify all points of interest within the crime scene. 

Note: Point of interest could be a specific location or item within a crime scene that holds potential evidentiary values. Example: victim’s body, weapon, bloodstains, points of entry or exit.

2. Establish search pathways marked by solid lines or other boundaries, which should not be crossed until necessary.
3. Begin the search at the first point of interest, such as the front door or an object, carefully documenting and processing the area before moving on to the next point.
4. Continue the search by moving from one point to the next, following a predefined path to ensure all critical areas are covered.
5. While searching, avoid straying from the searched pathways to minimize the risk of contaminating or losing potential evidence.
6. Once you reach the last point of interest, the process can be repeated to look for any unattended point of interest or evidence.

Example of Link (Point-to-Point) Search Method

I have listed two examples where link-based crime search methods can be used. The first case study is about homicide and the second is related to burglary.

Example 1: A Case of Homicide

A. Preliminary Search of the CS

In this case, a homicide is reported in a suburban house. Investigators arrive at the scene and identify several points of interest that need to be searched, documented, and processed.

1. The front door: Investigators notice signs of forced entry, such as a broken lock and scattered debris.
2. Body in living room: The victim is found on the sofa with multiple gunshot wounds.
3. The kitchen: Spent cartridge casings are discovered near the kitchen counter, indicating the shooter’s position.
4. Near the Kitchen: Additional cartridge casings are found near the entrance of the living room from the kitchen, suggesting that the shooter moved between rooms.
5. The back door: Investigators observe a partially opened back door, possibly indicating the shooter’s escape route.

B. Intrusive Search, Documentation, and Collection

In this scenario, investigators begin the point-to-point search method.

Step 1: Thoroughly document and process the front door, taking photographs, developing fingerprints using different brushes, and collecting other relevant evidence. 

Step 2: They then move on to the body in the living room, documenting and processing the scene, including the victim’s position, gunshot wounds, and surrounding evidence.

Step 3: Investigators move to the kitchen and living room, documenting and processing each area and collecting the cartridge casings. 

Step 4: Lastly, they move to the back door, examining the area for potential evidence and documenting any findings.

Read More: Grid Search Pattern Method: Procedure, When to Use With Examples

Example 2: A Case of Burglary

A. Preliminary Search of the Crime Scene

In another case of burglary case at a small jewelry store, investigators identify several points of interest:

1. Store entrance: The glass door has been broken, with glass fragments scattered around the area.
2. Jewelry Display cases: Several display cases have been forced open, and valuable jewelry items are missing.
3. Cash register: The cash register has been pried open, and the money inside has been taken.
4. Store office: The office door has been kicked in, and the safe has been tampered with but the safe is rigid enough to open.
5. Back exit: The back is opened and on the side wall there is a crowbar (maybe left behind by culprits).

B. Intrusive Search, Documentation, and Collection of Evidence

Step 1: Documenting and processing the store entrance, taking photographs with or without scales, collecting glass fragments, and finding possibilities of fingerprints as evidence.

Step 2: Proceed to the display cases, documenting the forced-open cases and any remaining jewelry items or evidence. This helps in claiming insurance, if any.

Step 3: Investigators now move to the cash register, documenting the scene and collecting fingerprints or any other evidence left behind. They found one set of fingerprints and developed it using magnetic powder and Magna brush and then lifted it using fingerprint lifters.

Step 4: Investigators move to the store office and look for the fingerprints but found nothing. Safe was photographs for damages.

Step 5: They examine the back exit, documenting the scene and collecting the crowbar as potential evidence. Crowbar has an erased serial number, it might be redeveloped and restored at the laboratory and might be used to trace back to culprits.

Read More: Spiral (Circle) Search Patterns: Procedure, When to Use With Examples

Advantages

• Helps establish clear walking paths, minimizing loss or destruction of evidence.
• Allows for a systematic search focused on multiple points of interest within the crime scene.
• Ensures that each point is properly documented and processed before moving to the next.
• Establishes walking paths throughout the scene, reducing the risk of contaminating or destroying evidence in unsearched areas.

Disadvantages

• In the case of many points of interest, the link method can be time-consuming.
• May not be effective for crime scenes with few distinct points of interest.
• Requires careful planning and execution to avoid crossing search boundaries or contaminating unsearched areas.

Precautions in Point-to-Point Search

1. Pre-search planning: Make a clear plan on what are the points of interest and how you’re going to process the crime scene.
2. Establishing search pathways: Define clear pathways between points of interest and look for any evidence that might be in the way.
3. Wear protective gear: All investigators should wear appropriate personal protective gear (gloves, shoe covers, and masks).
4. Adhering to search paths: Strictly follow the predefined paths during the search to prevent crossing into unsearched areas and potentially contaminating or losing evidence.
5. If additional equipment or supplies are needed, follow the established paths to prevent the loss or destruction of potential trace evidence.
6. Proper documentation: Thoroughly document each point of interest, including photographs, sketches, and detailed notes, before moving on to the next point.

Challenges in Point-to-Point or Link Crime Scene Search

1. Maintaining search boundaries can be challenging particularly in complex or cluttered crime scenes.
2. Incomplete search coverage might be a risk in link-based crime searches because even a single point of interest leads to losing evidence.
3. Coordination among investigators needs to be smooth and factful. Miscommunication can lead to missed evidence.
4. Investigators need to be flexible and adapt their search strategies according to the necessity of the crime scene.
5. Weather conditions can wash away the evidence and it is always challenging to search any crime scene.

General FAQs

References:

• Crime Scene Forensics: A Scientific Method Approach By Robert C Shaler [link]
• An introduction to crime scene investigation: AW Dutelle by Jones & Bartlett Learning
• Intelligent indexing of crime scene photographs by K. Pastra; H. Saggion; Y. Wilks [link]
• A Comparative Study: The Effectiveness of Various Search Strategies for Finding Critical Evidence in Crime Scene Analysis by Elianna Tracy, Spring Valley High School [link]
• Strip (Lane) Search Pattern: Procedure, When to Use? With Examples [link]