Timed scene processing
Use a paper-only fictional scene with coded cards, envelopes, and a scale drawing. Publish the scope, timing, permitted references, and approved accommodations before assessment. The student records a systematic search, item positions and limits, mock packaging, and custody handoffs. A supplied gap or unreadable feature must remain explicit; a timed exercise does not require a positive identification, chemical procedure, or real evidence.
| Criterion | Developing | Proficient | Mastery |
|---|---|---|---|
| Systematic search | Searches the scene at random and loses track of what has already been covered. | Has a rough plan but skips an area or re-covers ground already searched. | Works a logical search pattern, covering the whole scene once, and tracks what has been processed without gaps. |
| Evidence recognition | Ignores relevant supplied items or invents absent features. | Recognizes clear items but over-interprets unreadable detail. | Records relevant paper/image features, absent observations, and unreadable detail, explaining their relevance and detection limits without a guilt narrative. |
| Collection, packaging & custody | Handles or bags items in a way that risks contamination or loss, and logs nothing. | Collects and packages most items correctly but mislabels one or leaves a gap in the custody log. | Collects, packages, and seals each item in the right container, labels it, and opens a chain-of-custody entry for every piece. |
| Scene integrity under time pressure | Moves paper items before recording them or invents a missing handoff. | Records items but omits a cross-reference or unresolved gap. | Documents paper items before moving them, uses separate coded envelopes, retains custody gaps, and works within the disclosed timing and accommodations. |
| Documentation & justification | Records little, or states a conclusion the scene does not support. | Documents the main items but justifies a call with only one observation, or overstates what it proves. | Documents each item with sketch, photo, and note, justifies every collection decision, and states honestly what cannot yet be concluded. |
Integration is reported separately and cannot lower the science grade or block a science demonstration pass. Science and practical criteria determine that pass. Before assessment, publish the target list, task, permitted references, timing, and accommodations. Assess scientific reasoning and safe technique, not confidence or speaking speed.
“I preserved the scaled impression drawing and the original notes before moving the paper item. E-02 has a 20-minute unverified interval; I reported it without filling in a signature. A background or indirect transfer remains possible, so this record cannot identify a person’s actions.”
“I grabbed the stuff that looked important and put it in a bag. I didn’t photograph it first because I was running out of time, and I’m not sure what half of it means.”
Vary the paper layout and custody record from the published practice set, retain independent original work, and ask a fresh follow-up. Score scientific reasoning and documentation, not confidence or raw speed. The analyst reports evidence; the court decides guilt. No real samples, personal profiles, chemicals, firearms, ammunition, or projectiles are authorized.