Unit 2: Physical Evidences
2.1 Concept, Types and Importance of Physical Evidences
Physical evidence — the material traces of the crime: the objects carrying the information (against the testimonial evidence’s words). The types: biological (U4-U5: the blood, the semen, the DNA); impressions (U3: the fingerprints, the footprints, the tyre marks); trace (U6: the hair, fibres, paint, soil, glass); the arms-and-tool marks (U10); the documents (U9); the digital (the devices-and-data); the chemical (U7-U8: the toxins-and-drugs). The importance’s core: the objectivity (no motive-to-lie), the memory (the evidence persists when memories fail), the corroboration-and-contradiction (the testimony’s test), the reconstruction (the event’s scientific rebuilding).
2.2 Role of Physical Evidences in Administration of Justice
- The investigation’s compass — the leads-and-links (the suspect’s connection, the modus’s pattern).
- The prosecution’s proof — the case’s scientific spine (the identification, the reconstruction).
- The defence’s shield — the alibi’s-and-exclusion’s evidence (the innocence’s exonerations).
- The court’s certainty — the beyond-reasonable-doubt’s scientific support.
- The error’s corrector — the miscarriage’s undoing (the wrongful-conviction reversals — the DNA exonerations’ global record).
- The plea’s reality — the guilty pleas negotiated on the science (the trial’s avoidance).
2.3 Chain of Custody of Physical Evidences
The custody’s chain — the evidence’s documented journey: the collection (the officer, the time, the place); the packaging-and-sealing (the tamper-evidence); the labelling (the unique identification); the transport (the integrity’s protection); the storage (the security-and-preservation); the analysis (the examiner’s custody); the court’s production (the seal’s opening in court). The chain’s law: the break’s consequence — the admissibility-and-weight challenges (the tampering’s suspicion; the Evidence Act’s-and-procedure’s authentication faces); the record’s discipline (the custodial forms, the witnesses at every transfer). The exam’s line: the science is only as good as the chain.
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