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solving crimes with physics
sure. This is not to say that a wound to a major vein will not bleed heavily;
it certainly will. A deep gash to a major vein, such as the
superior vena
cava
, will result in a person losing enough blood to bleed to death in only
a few minutes.
The largest and most muscular blood vessel in a person’s body is the
aorta. This huge artery runs down through the ribcage and toward our legs,
where it splits into smaller arteries that supply blood to the legs. A wound
that opens the aorta will often result in death within seconds, not minutes.
Blood spatter analysis requires a sound understanding of human anat-
omy. This is because the amount of energy behind a spray or gush of
blood can be directly related to the circumstances of the wound—where the
wound is on the body, the type of weapon used to inflict the wound, and
the exact damage done to the body by the wound.
The Ways We Lose Blood:
Passive vs. Projected Blood
Not all wounds are created equal: some cuts bleed more than others. A
number of different types of blood loss are commonly associated with
crime scenes, each with characteristics that differentiate them from the oth-
ers. The type of blood loss is important information to investigators because
it can be used to make an educated guess about whether the wound was
inflicted intentionally, inflicted by accident, or self-inflicted.
In general, there are two main types of blood loss. Oozing blood is
the slowest and is most commonly found with shallow surface wounds like
scrapes. Generally speaking, oozing blood does not cause spatter unless it
flows for a long time. In these cases, it can drip off the person’s body and
fall to the floor, leaving behind a telltale trail of drops. Oozing blood often
