The wheel search method is used in crime scene investigation where there is a distinct central point. Here, investigators move from the center of the scene along linear paths like the spokes of a wheel toward the outer perimeter.
Other Names: Radial, Spoke, or Ray Search Pattern method of crime scene investigation.
Wheel or ray method is not suitable for investigating a larger crime scene. This is because many important evidence might get away between the rays.
When to Use Wheel or Ray Search Method?
Following are the areas where wheel crime scene search pattern can be used:
- Small crime scenes with limited area.
- Scenes with a distinct central point or focus.
- Explosion sites or impact zones.
- Body recovery in an open field or isolated location.
- Situations where a quick, initial search is needed before transitioning to a more thorough search method.
Procedure for Wheel Search Pattern Method
Following the procedure of wheel search pattern while investigating a crime scene:
- Identify the central point: Begin by identifying the central point or origin of the crime scene, which will serve as the hub for the wheel search pattern.
- Divide the area into sectors: Divide the crime scene into equal sectors, with each sector representing a spoke of the wheel.
- Assign investigators to each sector: Assign one or more investigators to each ray.
- Search along the spokes: Investigators should start at the central point and move outward along the imaginary spokes and progress towards the perimeter.
- Examine adjacent sectors: Once the investigators reach the end of their assigned spoke, they should carefully examine the area between their sector and the adjacent one to ensure no evidence is missed.
- Document and collect evidence: Document location, photograph it, and collect it using proper evidence collection techniques to maintain the chain of custody.
Read More: Zone Search Pattern Method: Procedure, When to Use With Examples
Practical Example of using Wheel Search Method
Case History: A child is missing in a small, isolated clearing in the woods when she was on a picnic with her family. Her mother told the police that she was playing nearby and she gets tied and sleeps.
So, So her mother falls asleep as well, and when she wakes up, she cannot find her. She called the police. There were wild animals too in the grasslands, police have to find her soon as the sun is going to set soon.
Why did investigators choose the Wheel search method?
Given the distinct central point and the necessity of finding it here soon, they choose the wheel search method. This is because, police have very less manpower, and their parents don’t know the direction where the child could go.
Police called for more men that can later be used to systematically search the area using line methods. But police have to do something asap, so they go with the wheel search method.
Step-by-Step Guidelines for Wheel or Ray Search Method
Step 1: Identify the Central Point
Determine the central point of the crime scene. In this case, the place where the child was playing.
Step 2: Divide the Scene into Sections
Divide the area into equal sections, resembling the spokes of a wheel. Each section should be manageable for a single searcher.
Step 3: Assign Searchers
Assign a searcher to each section or “ray” or “spoke.” In smaller teams, searchers may need to cover multiple sections.
Step 4: Conduct the Search
Searchers begin at the center and move outward along their assigned ray, examining the ground and surroundings for evidence.
Step 5: Sign and Evidence
As a sign, her whereabouts could at least define the direction she went or was taken away. Searchers should mark their location and notify the crime scene investigator for proper collection and documentation.
Step 6: Review the Search
Once all rays have been searched, regroup and discuss any findings. If necessary, repeat the search with additional searchers or alter the search pattern to cover any missed areas.
Read More: Dean Corll [The Candy Man Serial Killer]: Forensic Case Study
- Can cover a larger area in a short period of time.
- Easy to organize and doesn’t need sophisticated markings and zones.
- Can be considered if searching for larger visible evidence such as plane crash debris
- Not suitable for crime scene search. It should be considered the preliminary search method.
- There is always a need for a secondary and thorough search using other crime scene searching methods.
- Higher chance of missing potential evidence mainly between the areas of the two rays.
- Difficult to define confined boundaries.
How are sections or spokes determined in the wheel search method?
Sections are divided equally around the central point, with each section representing a manageable area for a single searcher.
How many searchers are needed for the wheel search method?
There are no minimum requirements. A number of searchers must only be given as per the rays needed to be searched. A minimum of 6 searchers would be effective to start with.
What if the crime scene has multiple central points?
Investigators may need to perform multiple wheel searches, each with a different central point, to ensure comprehensive coverage.
What if the wheel search method yields minimal evidence?
If minimal evidence is found, consider repeating the search or employing a different search pattern to ensure thorough coverage.
- Search theory: a mathematical theory for finding lost objects
- Techniques of Crime Scene Investigation By Barry A. J. Fisher, David R. Fisher [link]
- The Crime Scene: A Visual Guide By Marilyn T. Miller, Peter Massey [link]
- How to Search Vehicles for Evidence? A Practical Guide and Tips [link]
FR Author Group at ForensicReader is a team of Forensic experts and scholars having B.Sc, M.Sc, or Doctorate( Ph.D.) degrees in Forensic Science. We published on topics on fingerprints, questioned documents, forensic medicine, toxicology, physical evidence, and related case studies. Know More.