The Damp Denim Shirt: Wear, Sequence, and Packaging Damage

The evidence supports 'worn or draped over a body at the time,' but it does not prove it, and the answer should be phrased with that qualifier.

Pointing toward worn:

• Circular 1-3 mm droplets on the outer front placket and left chest indicate droplets landing on a surface roughly perpendicular to their flight. A shirt hanging or folded flat would collect them on whichever surface faced the source; a worn shirt collects them on the body-facing surfaces, in a distribution that follows body contours.
• The saturated right cuff with wicking halos indicates prolonged contact with a wet bloody source, which is consistent with a hand reaching into blood - compatible with the 'tried to help' account, and equally compatible with contact during an assault.
• The droplets and cuff saturation are on the same garment, in anatomically plausible places.

Complicating factors:

• The inner hem transfer (item c) means blood reached the inside surface. On a buttoned, worn shirt this is mechanically difficult except by soaking through. It is easier to explain if the shirt was open, partially off, or handled.
• 'Buttoned when submitted' describes the shirt at seizure, not at deposition. It proves nothing about the earlier state.
• Absence of staining on the collar's inner band is weak evidence either way; that area is often spared.
• The shirt was damp in a plastic bag for three days, so any original wet pattern has had time to migrate.

Conclusion: the outer droplet field and the cuff saturation are consistent with the shirt being worn during a blood-shedding event; the inner-hem transfer requires at least one separate contact event and raises the possibility that the shirt was open or removed. I would state exactly that, and decline to say 'he was wearing it.'

Largely no, and the reason is geometric rather than a matter of effort.

The two features are on opposite surfaces. Sequencing by superposition requires that two stains physically overlap on the same surface, so that one can be seen to lie over the other. Here the droplets are on the outside of the front placket and the transfer is on the inside of the hem. They do not intersect, so no direct ordering is possible.

What can be said:

• They represent at least two separate deposition events - a droplet-producing event and a contact-transfer event - unless the transfer is a soak-through from an external source, which should be tested by examining the matching external area for a corresponding stain and by looking at the dye and fibre behaviour at the boundary.
• If the droplet field and the transfer happen to meet anywhere, for example along the placket edge, low-power microscopic examination of the intersection can show which deposit lies on top and whether the underlying stain was wet at the time. That is worth doing before any conclusion is drawn.
• The very faint mirror-image stains on the back panel are a packaging artifact (see next question) and must not be sequenced against anything; they were created after seizure.
• On a porous, wicking substrate like denim, blood migrates along the fibres, so even a genuine overlap can be ambiguous. Wet blood on denim is a poor medium for fine sequencing.

Report language: the outer droplets and the inner-hem transfer are separate deposition events whose relative order cannot be determined from the available evidence. Offering an order here would be an overreach that a competent examiner would expose.

Effects on the evidence:

• Pattern distortion. Wet blood migrates through denim in three days. The mirror-image stains on the back panel matching the fold lines are the clearest sign: the shirt was folded or compressed while wet, and blood transferred across the folds. Those stains are an artifact of storage, not of the crime. They can mimic transfer patterns and, worse, they can overprint and obscure genuine staining.
• Biological degradation. Sealed damp, the shirt is an ideal environment for bacterial and fungal growth. DNA may be degraded, and bloodstains may discolour and become harder to interpret or to type.
• Contamination risk. A damp, sealed bag encourages transfer between areas of the garment and makes cross-contamination harder to exclude.
• Chain-of-custody and interpretation questions. Three days unaccounted for in a sealed bag invites a defence challenge that the patterns changed in custody.

What should have been requested:

1. Air-drying at room temperature, out of direct heat and sunlight, before packaging.
2. Packaging in breathable containers - paper bags or ventilated boxes - never sealed plastic for damp items.
3. Full photographic documentation with scale before packaging, plus documentation of the shirt's configuration (buttoned, folded, how folded).
4. DNA sampling coordinated with the pattern analysis, so that sampling does not destroy interpretable areas, with substrate controls.
5. A note in the report identifying the mirror-image stains as a storage artifact and excluding them from interpretation.

I would document the artifact explicitly, request repackaging now, and state in the report that the delay limits what can be said about the original wet patterns.