Cite this page: Harle L. Cause, manner and mechanism of death. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/forensicscauses.html. Accessed February 19th, 2019.
Mechanism of death
- Defined as the immediate physiologic derangement resulting in death
- Examples: hemorrhage, cardiac arrhythmia, cerebral hypoxia, sepsis
- A particular mechanism of death can be produced by a variety of different causes of death
Manner of death
- Defined as how the death came about; a judgment based on circumstances surrounding the fatal event
- In most jurisdictions the following categories are used:
- Natural: due entirely (or nearly so) to natural disease processes
- Homicide: due to a volitional act of another person with the intent to cause fear, harm or death
- Homicidal manner does not indicate a criminal homicide, which is determined by the legal process and not by the certifier of death
- Suicide: due to injury that occurred with the intent to induce self harm or cause one's own death
- Accident: due to injury when there is no evidence of intent to harm
- Undetermined: inadequate information regarding the circumstances of death to determine manner; example: individual found unconscious with massive subdural hemorrhage; in the absence of information on the events leading up to death, it is impossible to determine if the hemorrhage is due to accidental fall, homicidal violence, etc.
- When death is due to a combination of natural and unnatural events, preference is generally given to the nonnatural cause; example: a man suffers a myocardial infarction while swimming in the ocean, loses consciousness, and drowns; the manner of death is ruled accident, as he may potentially have survived if the fatal myocardial infarction had occurred on land
- The "but for" principle asks the question "But for the inciting injury (or event), would the decedent still be alive?"
- In most jurisdictions, deaths due to motor vehicle collisions are considered accidental in manner
- Deaths due to complications of medical therapy that are reasonably expectable (e.g. neutropenia due to chemotherapy, digoxin toxicity) are considered natural
- Deaths due to improper use of medical devices or improper therapy (e.g. malfunctioning morphine drip, failure to repair obvious arterial injury inflicted during surgery) are considered accidental
- While acute alcohol or drug toxicity is considered an accidental death, deaths due to consequences of chronic substance abuse (hepatic cirrhosis due to ethanol abuse, endocarditis secondary to IV drug use) are conventionally considered natural in manner