Classification of crime scene and search method

Classification of crime scene

Objectives –

• What is crime scene

• Different types of crime scene on different basis

• Different types of search methods

What is crime scene –

• A place where the crime is committed or where the maximum physical evidence related to crime is found is known as a crime scene.

• A crime scene is a starting point of the investigation which provides information about the suspect and the victim.

• crime scene is not limited to a single place but may extend to a wider area depending upon the nature of the crime committed.

• So lets know about the different types of crime scene-

Types of crime –

1. Based on evidence found on the crime scene:

• Primary

• Secondary

2. Based on the geographical location of the crime scene:

• Outdoor crime scene

• Indoor Crime Scene

• Mobile/ Conveyance Crime Scene

3. Based on the size of the crime scene

• Microscopic Crime scene

• Macroscopic Crime scene

Based on evidence found on the crime scene –

1. Primary crime scene

• The crime scene where the actual crime occurred or where more usable pieces of evidence were found is known as the primary crime scene.

• For example, A murder scene, theft, etc.

2. Secondary crime scene

• The crime scene which is some or another way related to the crime but is not a place where the actual crime is committed is known as a secondary crime scene.

• Example- place where planning is done, place where person is killed but moved to secondary place like forest/river etc.

Based on the geographical location of the crime scene –

1. Outdoor crime scene

• A crime that is committed in an open and wide area like a field, park, road, playground, etc. is known as an outdoor crime scene.

• It is more vulnerable to loss or contamination of evidence by sunlight, air, or extreme weather.

• . Grid or strip search method provides a better result to find evidence at an outdoor crime scene.

2. Indoor Crime Scene

• A crime that is committed in an enclosed and small area like a room, hall, corridor, kitchen, etc. is known as an indoor crime scene.

• It is less vulnerable to contamination as it would not have much effect from outside environment.

• Spiral, circular, and zone search methods provide better results to find evidence at an indoor crime scene.

3. Mobile/ Conveyance Crime Scene

• Crimes that are committed in conveyances include the following: Vehicle, Train/Bus, Lift, Flight.

• Example- theft in train\bus, rape in any vehicle etc.

Based on the size of the crime scene –

1. Microscopic Crime scene

• Evidence is examined at a very small scale, often requiring the use of specialized tools such as hand lens.

• Focuses on tiny particles, Fibers, hairs, bloodstains, and traces left behind at the crime scene.

• Example- hair on hair brush, nails of dead body on the crime scene etc.

2. Macroscopic Crime scene

• Macroscopic crime scenes involve the examination of evidence at a larger scale.

• This includes observing bloodstains, footprints, weapons, broken glass etc.

Searching methods –

Search techniques vary from one scene to another and also vary on the personal choices of investigator-

1. Zonal searching method

2. Spiral searching method

3. Strip/ line searching method

4. Cross hatch/ grid searching method

5. Wheel / ray searching method

1. Zonal searching method

• Crime scene is divided into small zone and each zone is examined separately.

• No. of zone depend on the area of crime scene

• It is mostly used for open and big crime scenes

2. Strip/ line searching method

• Searching in a parallel raw by covering whole area by moving in strips from first point to second and then again to first point but with next line/strip

• Useful for large areas

3. Spiral searching method

• It is carried out by either from outside or inside(from center) in a spiral form with either increasing or decreasing circumference.

• Used for small areas like a room

4. Cross hatch/ grid searching method

• It is a variation of strip method where investigator search same area multiple times

• Usually done for large areas where chances of missing any evidence is high

5. Wheel / ray searching method

Best method where area is kind of circular boundary, in this method investigator starting at the center of the scene and moving outwards along path that resembles to spokes of a wheel

Classification of crime scene and search methods