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satyesu
03-11-2015, 02:26 AM
I'm putting together a murder mystery in my Dungeons & Dragons game where a father beats his son to death and then soon after slashes up the body to make it look like a clawed monster in the back woods did it. Would the bruises form soon enough to still be on the body? If the slash was made along the bruising, would it show on the edges of the cut?

blacbird
03-11-2015, 02:43 AM
All bruising is pre-death. A body doesn't bruise after death. And any half-way competent medical examiner can easily determine if slashes or stabs are inflicted post-mortem.

caw

satyesu
03-11-2015, 02:51 AM
In an archived thread I found on Google someone said if blood pooled after death it would be similar to pre-mortem. The setting's tech level is too low for comparison to today's forensics.

jclarkdawe
03-11-2015, 03:18 AM
How dumb do you want the medical examiner?

Once the heart stops beating, blood flow ceases other than as a result of gravity. In a living body, blood will flow uphill and be forced out any cuts. In a dead body, you can get blood to flow out only through gravity, which is why hunters hang meat.

Any hunter or butcher can tell the difference.

Let's say a body is lying face up on the ground and dead. You slice across the stomach about an inch deep. If you then pull the skin open from the slice, you'll see very little if any blood. Normally, in a living human, this wound will bleed a lot.

Bruising after death shows up by observing the damaged cells. There is again little or no blood that will be in the bruised area.

Even if you cut in an area where there will be bleeding from the pooled blood because of gravity, the flow will be markedly different than in a living human. Blood in a living human is at a pressure of 2.32 psi/1.55 psi (120/80). Gravity flow will be at less than 1.00 psi. In a dead body, it's going to ooze more than flow because of this lack of pressure.

Whoever said that post-mortem pooled blood would mimic pre-mortem blood in flow is either making a very qualified statement or doesn't know anything about autopsies.

Best of luck,

Jim Clark-Dawe

satyesu
03-11-2015, 03:32 AM
Thanks!

cornflake
03-11-2015, 06:39 AM
In an archived thread I found on Google someone said if blood pooled after death it would be similar to pre-mortem. The setting's tech level is too low for comparison to today's forensics.

Lividity and bruising are not at all the same.

There's also tissue damage, bruising or not, that'd likely be observable. As jack said, you'd have a heck of a dumb me to not be able to tell pre- from post-mortem.