Estimating the Time of Death: Livor Mortis

Livor mortis, often referred to as postmortem lividity, is a purplish discoloration of the skin following death. The discoloration is a result of blood pooling in the lower parts of the body. You see, once the heart stops pumping, gravity will force the blood to seep into these lower areas. Lividity will not form in areas of the body pressing hard against the floor because the pressure against the capillaries won’t allow the blood to settle.  Instead, these areas will result in a white coloration called blanching.  You can mimic this effect by gripping your forearm tightly with your opposite hand. Squeeze tightly for a few seconds and then release. You should see a whitish coloring where your fingers were.

Lividity is important to the investigator for two reasons. First, it can provide investigators with a general understanding of the time since death. These estimates are influenced by things such as temperature, body mass, conditions at the crime scene, and other factors. Suffice it to say I’m only giving you very general time frames but for your novel they should be fine.  Lividity is generally seen within the first 1-2 hours following death. It will typically become fully developed within 3-4 hours but could still be altered if the body position changed. After 12 hours the lividity becomes fixed meaning it will not change.

As I have just alluded, there is another important reason for investigators to note postmortem lividity. It can indicate a change in body position. If, for example, your detective finds a body face up with the purplish color face up as well; it’s a clear indication that the body was turned over several hours after death.  Investigators can also use the areas of blanching to help reconstruct the original position of the body. Blanching might even indicate another location or crime scene.  Hypothetically, if you were to see 4″ wide slots of blanching separated by thin purple lines that may indicate your body was laying on a wooden deck made of 2x4s.

You might be asking yourself why a suspect would wait several hours before turning a body. One possibility is that they returned to the scene for some reason. They may have forgotten something or decided later on to come back and remove evidence like shell casings that might be used to implicate them.

Lower legs showing both lividity and blanching

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About forensics4fiction

Hi there. Thank you for visiting my BLOG for crime writers. I hope you will find it interesting. I would love to hear your questions and thoughts regarding forensics and criminal investigations. I hope that the information here will help answer your questions or ignite your imagination. I am a retired senior criminalist with 15 years of forensic experience. I have served as the president of the Association for Crime Scene Reconstruction, Rocky Mountain Association of Bloodstain Pattern Analysts, and the Rocky Mountain Division of the International Association for Identification. I am triple board certified in forensic related fields and one of only 40 board-certified bloodstain pattern analysts and 80 board-certified footwear examiners worldwide In addition to writing over 60 scientific papers, I have worked as the editor of the Journal of the Association for Crime Scene Reconstruction, been interviewed by and consulted for television, books, magazines, and newspaper articles including documentaries on the Discovery Channel and National Geographic.

Posted on June 6, 2011, in The Autopsy, The Crime Scene and tagged , , , , , , , , , , , , . Bookmark the permalink. 11 Comments.

  1. Very interesting article, f4f. This was something I only knew a very little about. You’ve filled in the gaps and now I want to write a story that is solved by looking at the postmortem lividity. You say that once the lividity is well established, it remains the same from then on? It doesn’t ever go away?

    On another topic, what about the stiffness of a corpse? How long before that starts, how long does it last, and what is the correct name of the condition?

  2. Oops, I just remember the correct name of the stiffness…rigor mortis. How could I forget that? lol

  3. It takes about 3-4 hours to become well established (meaning clearly visible/formed) but research has shown that if the body is moved at this point there can be additional areas of lividity formed. Truthfully, there hasn’t been a lot of case studies on this phenomenon because it’s rare in criminal cases. However, it is possible. After 12 hours it becomes fixed and will stay that way (regardless of body movement) until decomposition makes it unrecognizable.

    The stiffening of the body is called rigor mortis and I’ll be covering that in another post.

  4. I have to ask — do you know what is responsible for the odd blanching on the body in your photo? It seems like there’s an odd story there…

  5. The blanching is from pressure points made by the body laying on certain objects. I generally don’t go into many details about photos (out of respect) but think about a person that collapses on the floor if that floor is littered with other household items. For example, if the body laid on the remote control which was on the floor you’d see a blanching of that controller in that location. Now if we see blanching of something that is not under the body (like the wooden deck example in the story) then we can surmise that the body had been moved after fixation. Does that clear it up any? As an author you can use the shape of an object (represented by blanching) to demonstrate something was taken, which also might explain why the body was moved hours after death. For example, if you saw a body with a blanching in the outline of a gun but the gun wasn’t there you could conclude that the victim laid on the gun (causing the blanching) and then, hours later, the suspcet or someone else perhaps (kids finding a body in a public place like a park) removed the gun.

  6. Hey. I was wondering if the top image of livor mortis was your own? If so can I possibly use it for a university poster?
    If not, do you know the source of the image?

  7. The image is my own but I do not authorize any use of images from forensics4fiction for other uses. I am sorry. You might want to check with your professor to see if they know any local coroners or look to see if your state has a coroner’s association that may be able to assist you.

  8. On my book, the night is very cold. The victim’s throat is slit open. The body is then moved and placed sitting on a bench, still in the open. After 4-6 hours, what will the exposed skin of face and semi-exposed neck look like. Most grateful for your help
    Rosalind

  9. Great question. Whenever bodies with major blood loss are moved there is the potential for additional blood loss (thru gravity) that will be inconsistent with the final position. For example, placing the body in a vehicle trunk may jostle the corpse as does getting it in and out from one location to another. If the victim was killed while sitting on the bench then one would expect most of the blood flow to go outward and downward (mostly). So seeing a blood flow to one side or upwards to the head would be considered a red flag. Blood is very tacky so there is also the possibility of retaining fibers, hairs, and patterns (carpet) in the actual stain. As for the body appearance. You wouldn’t see anything “abnormal” in decomposition. In terms of lividity, it will not have had a chance to set up well after 5 hours, especially if the body has been in transport. Hope that helps, Tom

  10. dadareyes@shaw.ca

    I am very grateful to you, Tom. That is most helpful Rosalind

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