Incoming cases matched to the corpus

Historical reports referenced

1. 1.N(T) 1287/20

   Strong relevance

   RFSL Nagpur · 2020 · Ballistics

   Same division of examination (Ballistics). Shared case terminology: revolver, cartridge, bullet, murder, firing. Comparable exhibit types: calibre, revolver, fired, cartridge, indentation. Methodology already applied here: Comparison microscopy, Test firing, Walker's test / modified Griess test for nitrite.

   Methods on file: Comparison microscopy, Test firing, Walker's test / modified Griess test for nitrite, Examination for metallic lead and powder residue

2. 2.RFSL/AMT/BAL/2025/1262

   Strong relevance

   RFSL Amravati · 2025 · Ballistics

   Same division of examination (Ballistics). Shared case terminology: cartridge, firing, residue, test. Comparable exhibit types: calibre, deformed, lead, bullet, recovered. Methodology already applied here: Test firing, Walker's test / modified Griess test for nitrite, Comparison microscopy.

   Methods on file: Test firing, Walker's test / modified Griess test for nitrite, Comparison microscopy

3. 3.RFSL/AMT/BAL/2017/0741

   Strong relevance

   RFSL Amravati · 2017 · Ballistics

   Same division of examination (Ballistics). Shared case terminology: bullet, firing, residue, test. Comparable exhibit types: calibre, fired, cartridge, indentation, percussion. Methodology already applied here: Comparison microscopy, Walker's test / modified Griess test for nitrite.

   Methods on file: Comparison microscopy, Walker's test / modified Griess test for nitrite

4. 4.RFSL/KOP/BAL/2017/3815

   Strong relevance

   RFSL Kolhapur · 2017 · Ballistics

   Same division of examination (Ballistics). Shared case terminology: cartridge, bullet, test. Comparable exhibit types: calibre, revolver, working, condition, deformed. Methodology already applied here: Comparison microscopy, Test firing.

   Methods on file: Trigger pull and serviceability testing, Comparison microscopy, Test firing

5. 5.RFSL/AMT/BAL/2021/2184

   Strong relevance

   RFSL Amravati · 2021 · Ballistics

   Same division of examination (Ballistics). Shared case terminology: cartridge, bullet, residue. Comparable exhibit types: calibre, revolver, working, condition, fired. Methodology already applied here: Test firing, Walker's test / modified Griess test for nitrite.

   Methods on file: Trigger pull and serviceability testing, Test firing, Walker's test / modified Griess test for nitrite

Methodological parallels

• ·N(T) 1287/20 (2020) applied Comparison microscopy, Test firing, Walker's test / modified Griess test for nitrite on comparable material.
• ·RFSL/AMT/BAL/2025/1262 (2025) applied Test firing, Walker's test / modified Griess test for nitrite, Comparison microscopy on comparable material.
• ·RFSL/AMT/BAL/2017/0741 (2017) applied Comparison microscopy, Walker's test / modified Griess test for nitrite on comparable material.
• ·RFSL/KOP/BAL/2017/3815 (2017) applied Trigger pull and serviceability testing, Comparison microscopy, Test firing on comparable material.
• ·RFSL/AMT/BAL/2021/2184 (2021) applied Trigger pull and serviceability testing, Test firing, Walker's test / modified Griess test for nitrite on comparable material.

Technology evolution notes

• ABO grouping by absorption-elution (Serology and biology)

  ABO grouping by absorption-elution was standard practice until roughly 2012. Current laboratory practice has moved to Presumptive screening followed by STR profiling of the same stain for individual level association.

  Seen in R01, R055, R040, R085, R116

• Walker's test / modified Griess test (Ballistics and firearm discharge residue)

  Walker's test / modified Griess test remained in routine use until roughly 2018 as a stand-alone residue finding. It is still defensible for continuity, and current practice adds SEM-EDX for characteristic lead, barium and antimony particles, supported by the chemical test as a screen.

  Seen in R01, R055, R040, R116

Indian Evidence Act and related provisions

• Section 293, Indian Evidence Act, 1872 · Reports of certain Government scientific experts

  A report signed by a listed Government scientific expert, which includes Chemical Examiners and officers of the Forensic Science Laboratory, can be used as evidence without calling the officer into the witness box. The court still has discretion to summon the officer, and the accused retains the right to ask for the expert so that the report can be tested in cross-examination.

  Why it matters: Most laboratory reports enter the record through this route. Clean documentation, an identifiable signatory with designation, intact seals and a complete exhibit register are what make the court comfortable relying on the report as it stands.

• Section 45, Indian Evidence Act, 1872 · Opinions of experts

  When a point involves specialised knowledge such as science, art, handwriting or finger impressions, the opinion of a person skilled in that field is relevant. The opinion carries weight in proportion to the reasoning and data shown behind it.

  Why it matters: The opinion paragraph should be traceable to observations, methods and instrument data recorded in the same report. A conclusion stated without the supporting steps is easy to attack.

• Section 294 CrPC, Code of Criminal Procedure, 1973 · No formal proof of certain documents

  If the genuineness of a document is not disputed by the other side, formal proof can be dispensed with and the document read in evidence.

  Why it matters: Where the defence admits the laboratory report, the examination proceeds without the officer attending, which shortens the trial.

Chain of custody observations

• Condition on receipt: Seals recorded as intact and tallied with the specimen seals on receipt.

Laboratory practices referenced

• · Results are reported only for the exhibits actually examined, with remnants resealed and entered in the register.
• · Method, kit or tool version, and instrument identity are recorded so the examination can be repeated or reviewed.
• · Screening tests are treated as presumptive and carried through to instrument or profile level confirmation before any opinion.
• · The signatory records name, designation and division, which is what a Section 293 report needs on its face.

Limitations and gaps identified

• ·No material gaps identified in the referenced files or in the custody record for this case.