Search Pattern
Definition
The systematic geometric route walked by a dog handler to ensure uniform coverage of the search area. Standard patterns include the ladder (parallel transects) and the spiral (inward from the boundary). Pattern choice depends on wind direction and terrain.
- Core purpose
- Ensure complete scene coverage without gaps or redundant searching
- Key pattern types
- Strip, grid, spiral, zone, wheel, ladder (for canine searches)
- Selection factors
- Scene size, shape, terrain, number of searchers, wind direction (canine)
Common questions
What is a search pattern in forensic investigation?+
A search pattern is a predetermined systematic method for traversing a crime scene to ensure complete coverage without gaps or re-treading ground. The pattern chosen depends on the scene's size, shape, terrain, and the number of searchers available. Common patterns include strip, grid, spiral, zone, and wheel searches.
How do you decide which search pattern to use?+
The choice of pattern is driven by practical scene characteristics. For large open areas, strip or grid patterns work well with multiple searchers. Spiral patterns are effective for circular or bounded areas. In canine searches, handlers choose between ladder (parallel transects) and spiral patterns based on wind direction and terrain to ensure uniform coverage.
Why does search pattern matter in forensic investigation?+
A predetermined movement plan prevents searchers from missing evidence, duplicating effort, or wasting time. It ensures the entire area is examined exhaustively and systematically, which is essential for thorough evidence recovery and maintaining the integrity of the investigation.
Related terms
- Bindle
- A small tamper-evident paper packet folded to contain trace evidence. All four edges are tucked inward so no material can escape and...
- Centrifugal Spiral
- Spiral that starts at the centre of the scene (usually the body) and moves outward. Preferred when the central evidence is fragile...
- Centripetal Spiral
- Spiral that starts at the perimeter and moves inward toward the focus. Preferred when perimeter evidence is at risk from weather or...
- Exhibit Number
- The unique reference code assigned to each recovered item at the moment of collection. It appears on the label, in the scene...
- HRD Dog
- Human Remains Detection dog: a dog trained to detect and alert on the volatile organic compound signature of decomposing human tissue. Also...
- Passive Alert
- A trained response in which the dog sits, lies down, or freezes at the scent source without digging or pawing. Preferred in...
- PPE (Personal Protective Equipment)
- Gloves, scene suits, overshoes, and masks worn by scene examiners. PPE protects the examiner from hazardous substances at the scene, and protects...
- Primary Container
- The packaging that is in direct contact with the evidence item: a bindle, an evidence bag, a rigid box. The primary container...
- Scent Cone
- The plume of airborne VOC molecules that diffuses upward and downwind from a buried source. A dog working downwind of a buried...
- Tile Probe
- A solid steel rod used to probe suspect ground by hand pressure, detecting resistance changes in disturbed soil and releasing sub-surface gases...
- VOC (Volatile Organic Compound)
- Carbon-containing compounds that evaporate readily at ambient temperatures. Decomposing human tissue produces a complex, changing VOC mixture that HRD dogs are trained...
- Wedge Problem
- Inherent flaw of wheel search: as spokes radiate outward, the unsearched gap between adjacent spokes widens with distance from the centre.
Explained in these topics
- Canine Search and ProbingThe systematic geometric route walked by a dog handler to ensure uniform coverage of the search area. Standard patterns include the ladder (parallel transects)...
- Crime Scene Search Techniques (Strip, Grid, Spiral, Zone, Wheel)A predetermined movement plan that one or more searchers follow to examine a defined area exhaustively, without gaps and without re-treading covered ground.
- Search, Collection, Packaging and PreservationA systematic method for traversing a scene to ensure complete coverage. The choice of pattern is driven by scene size, shape, terrain, and the number of availa...