You've helped them one at a time. The real understanding is how the ideas CONNECT — teach that next.
Sketch (scene documentation — record the scene before anyone touches it) ×Seal (chain of custody — log every hand the evidence passes through)
Both Sketch and Seal exist to stop the same disaster. What is it?
Sketch then says: “Once the scene is photographed (Sketch), I don't need to log who handles the evidence.” — is that right?
The link: document at the source, then track every hand — two guards on one thing: trust.
Record it, then never lose track of it.
Branch (alternative explanations — test each "what else could explain this?") ×Account (testimony reliability — memory is fragile; a confident witness can be wrong)
A witness is very confident. Why does Branch make you slow down before believing Account?
Branch then says: “The witness is absolutely sure, so we can stop investigating and name the suspect.” — is that right?
The link: a confident account is a starting point, not a verdict — Branch keeps it honest.
Hear the witness, then test what else could be true.
Capstone — work one case together
Three moves of a clean investigation. Bring in the cast member for each.
Before anyone touches the room, record where everything is. Who?
Who do you bring in?
A single hair links the suspect to the scene — every contact leaves a trace. Who names the principle?
Who do you bring in?
A confident witness names someone; before believing it, test other explanations. Who?
Who do you bring in?
The synthesis: preserve the scene, follow the physical trace, and never let one confident story skip the alternatives — that's how a case holds up.
Document, trace, and test — evidence that survives court.
