Skill 12 of 30

Pattern, impression and physical evidence

Bloodstain Pattern Documenter

Help a trained examiner record bloodstain-pattern observations consistently and trace every measurement to its source image and location.

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AI-assisted draft. Not a forensic conclusion.

Use this skill only with authorised material and within the user's role, competence, jurisdiction, laboratory procedures and information-handling rules.

When to use this skill

Create standardised bloodstain-pattern documentation, measurement inventories, image links, and expert-review worksheets. Use to support trained BPA personnel; not to classify mechanisms or reconstruct violence autonomously.

What to provide

  • original and scaled images
  • scene plan and orientation
  • examiner annotations
  • surface and location information
  • approved BPA terminology and procedure

If a material input is absent, it should remain marked as unknown. The skill must not reconstruct missing facts from narrative fit.

Method

  1. Inventory pattern locations, surfaces, images and scales.
  2. Record size, shape, distribution, appearance, directionality data, voids and limitations using approved terminology.
  3. Link every measurement to an image, region and examiner annotation.
  4. Separate recorded observation, calculation, classification and event interpretation.
  5. Record plausible competing mechanisms without selecting among them, and identify the observations or tests a qualified examiner would need to distinguish them.
  6. Record non-conforming material, preservation action, missing measurements, context and technical-review needs in the limitation register.

Direct observations, reported facts, test results, expert interpretations, hypotheses, unknowns, conflicts and exclusions must remain in separate fields.

Outputs

  • BPA documentation worksheet
  • measurement and image-reference table
  • pattern-location map
  • limitation register
  • expert-review questions

Every material statement should cite an exhibit, file, page, image, timestamp, record, standard or named assumption.

Hard limits

  • Do not automatically classify pattern mechanisms or reconstruct acts of violence.
  • Do not infer blood origin or identity from appearance.
  • Do not present general-purpose image measurements as validated BPA results.

The skill must not determine guilt, recommend arrest or coercive action, invent evidence, backfill records, promise admissibility or hide potentially exculpatory, adverse, inconsistent or limiting information.

Required human review

Reviewer: Qualified bloodstain-pattern examiner and technical reviewer.

The reviewer must approve, amend or reject each material observation and interpretation before operational, laboratory, prosecutorial or court use.

Sample prompt

Use $bloodstain-pattern-documenter to create a measurement and image-reference worksheet without classifying the mechanism.

Skill source files

Skill instructionsScope, intake, method, outputs, limits and review requirements OpenAI metadataDisplay name, description and default prompt Discipline guidancePrimary publications and controls specific to this skill Core forensic workflowEvidence states and the shared output contract Safety and human reviewProhibited uses, scientific controls and reviewer levels India legal layerBNSS, BSA, MHA and local implementation controls

View the complete Forensic AI Skills project on GitHub.