Break-In at 214 Alder
A rear door has been forced; the complainant waits out front. Seven steps are available: A. Photograph the exterior and the point of entry before anyone enters. B. Set an inner perimeter and open a scene-entry log. C. Interview the complainant away from the door. D. Swab the tool mark on the rear door for DNA. E. Dust the same door surface for latent prints. F. Package and seal each collected item. G. Submit the sealed items to the property room. Posted practice: the scene is photographed before entry; everyone who enters signs the log; DNA swabbing must precede fingerprint powder on the same surface because powder degrades DNA; packaging follows collection; property submission is last; interviews may occur at any point before the scene is released.
1. Give one valid complete order of A through G and identify any step whose position is flexible.
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Valid order: B → A → C → D → E → F → G
Why each placement holds:
- B first: the perimeter and entry log must exist before bodies move through the door, or the log records nothing worth recording.
- A before entry: the posted practice is explicit that photography precedes anyone entering.
- D before E: powder degrades DNA, so swab the tool mark before dusting the same surface. This is the ordering constraint most likely to be tested.
- F after D and E: nothing can be packaged before it is collected.
- G last: property submission is the terminal step.
Flexible step: C. The interview may occur at any point before the scene is released, so it can be moved to the front (before B) or to the end (after F) without breaking any posted constraint. It should stay away from the door so the complainant does not contaminate the entry path.
2. The tool mark sits on the latch plate, which is also the most likely surface for prints. Does that change the order?
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No - D still precedes E. The posted practice is a same-surface rule, and the tool mark and the print surface are the same surface here. That strengthens the rule rather than suspending it.
What does change:
- The swab and the dusting now compete for one small area, so the officer should document the sequence (photographs before and after each technique) so a later challenge cannot claim the print was destroyed by the swab or the DNA by the powder.
- Any other print-bearing surfaces - the door handle, the frame, the interior side - should be processed so the case does not depend solely on a contested latch plate.
- If laboratory guidance for this substrate conflicts with the posted order, the conflict should be noted contemporaneously rather than resolved silently in the field.
Reasoning point: a constraint that becomes inconvenient does not disappear; it becomes something you document.
3. A sergeant says the entry log is unnecessary because only two people will enter. How should the officer respond?
Read the worked answer
The log stays. The posted practice requires everyone who enters to sign; "only two" is still two unsigned entries if the log is skipped.
Why it matters beyond rule compliance:
- The log is the department's answer to a contamination or planted-evidence challenge months later. Without names and times, the officer cannot show who was inside or when.
- Two entries are the easiest case to log, not the hardest - the cost is seconds.
- Skipping it also undermines the perimeter set in step B, since the log is the mechanism that makes the perimeter meaningful.
Practical move: log both entries, note the sergeant's presence if the sergeant enters, and keep C flexible so the complainant interview does not force extra traffic past the door.