Sources:“A Closer Look On Forensic Science“ written by Archana Singh
🔦WHAT IS PHYSICAL EVIDENCE?
✔Physical evidence is any object that can establish that a
crime has been committed or can link a crime and its victim or perpetrator.
✔Anything can be physical evidence which can connect crime scene to criminal.
✔“In simple words to count physical evidences cannot be possible.”
🔦Types of Physical Evidences
Body fluids or materials found at a crime scene might include ::
🔘In case of poison main parts of body such as Liver, Gall bladder, Brain, Kidney, Small intestine, Pancreas, Uterus, Heart and Lungs should be analyzed.
🔘Blood, Semen, Saliva and Vomit in dry or liquid state.
🔘Hair, Nails, Skeleton, Bone.
3. CHEMICAL SUBSTANCE:
🚫EXPLOSIVE- any object that has a residue of an explosive is useful.
🔑Other arms, such as;
5. DISPUTED DOCUMENTS:
Examinations and comparisons conducted by document examiners can be diverse and may involve the following:
- Typewriters, photocopiers, printers, fax machines.
- Handwriting (cursive / printing) and signatures.
- Alterations, additions, erasures, obliterations.
- Indentation detection and/or decipherment.
- Cheque writers, rubber stamps, markers.
- Physical matching.
- Ink, pencil, paper
6. PETROLEUM SUBSTANCE:
⚫Any type of petroleum substance which is likely related to criminal act.
Such as kerosene oil, petrol, etc.
7. TOOL MARKS:
⭕Tool mark as any impression, cut, gouge, or abrasion caused by a tool coming into contact with another.
⭕They consist of small, commonly microscopic, indentations, ridges, and irregularities present on the tool itself. For example, the tip of a screwdriver is never perfectly flat, but shows small ridges along its edge.
9. FIBERS AND TEXTILE:
🧤In Many Cases, Clothes And Rope Are Used In Many Forms.
🔅Which stick with Tiers, Mudgaurd, Shoes, Clothes, etc.
🔎Pieces of glass ,such as
🔎Any Window/ Glass Door
12. OBJECTS OF CRIMINAL:
13. OTHER EVIDENCE:
◾Any other substances found on crime scene not described before in previous slides should be considered of this category.
◾For ex after collision of new building or bridge, sample of debris is physical evidence.
◾Things which have numbers. Like, engine, chesis, etc.
🔦Information that can be obtained from Physical Evidence
⚀The Latin term corpus delicti refers to the principle that there must be some proof that a crime has been committed before a person can be convicted that crime.
⚀Corpus delicti literally means body of crimes.
📍Identification of suspect:
Fingerprints are valuable evidence to identify and individualize suspect.
📍Linking suspect with victim:
At the time of crime blood, hair, fiber, etc. can be exchange between suspect and victim which establishes connection.
📍Linking of suspect with scene of crime:
Fingerprints, shoeprint or footprint, blood, semen, fiber, hair, tool marks, tier impression, bullet, soil ,etc. are evidences which can establish links from suspect to scene of crime.
📍Providing investigative leads:
Physical evidences leads police officers in criminal investigation.
📍Information about modus operandi:
Criminals, specially habitual criminals have same type of crime manner. Same criminal pattern of behavior helps to caught criminals.
📍Verification of statement:
Statement of person(victim, witness, criminal) can be tested After examination and reconstruction of physical evidence.
🔦Nature of Physical Evidence
A. Identification by class characteristics-
Every item has a measurable features of an item that indicate a restricted group source based on design factors determined prior to manufacture.
✔Physical evidences first identify by its class characteristics.
B. Comparison and individualism-
Marks on an object produced by the random imperfection or irregularities on the surfaces of the tools used to manufacture the object.
✔Individual characteristic confirm the object.