Forensic thanatology is concerned with the medicolegal study of death.
Death can be defined as the complete and irreversible cessation of body functions especially brain, circulation and respiration, following modern resuscitation attempts.
Concept of Brain Death
It is the criteria set by Adhoc Committee of the Harvard Medical School to Examine the Definition of Death (1968).
- Un-receptivity and un-responsiveness, including a total lack of response to the most intense, painful stimuli.
- No movements or breathing. No effort to breathe for 3 minutes off the respirator with the patients carbon dioxide tension normal and room air being breathed for ten minutes prior to the trial.
- No reflexes –fixed non reactive pupils, lack of cranial nerve reflexes (corneal, pharyngeal, ocular movements in response to head turning and irrigation of ears with ice water, etc.)(Brain stem death)
- Isoelectric electroencephalogram (EEG)
Cause of Death
On the basis of cause death can be classified as due to:
- Diseases –natural deaths
- Trauma or poisons –unnatural deaths
Manner of Death
It is important as has legal consequences.
i. Culpable -Murder or manslaughter
ii. Non culpable –Justified (judicial hanging) or excusable (self defense)
Mode of Death
- Coma –death from failure of functioning of brain
- Syncope –death from failure of functioning of heart
- Asphyxia –death from failure of functioning of lungs
Mens rea –“Guilty minded” or “evil thought”
Actus rea –“Actual physical act”
It must be determined, if the person has committed crime by his will or evil thought. A child is not held responsible for a murder as he/she cannot have an evil mind. The intention is judged by circumstances.
Circumstances must prove that the person was not able to understand to consequences of his/her act. Protection is provided to mentally ill patients.
Stages of Death
1. Somatic or Clinical Death
All vital functions such as circulation and respiration cease to function
2. Molecular or Cellular Death
Tissues and constituent cells are no longer functioning metabolically. It completes in 3-4 hours after somatic death.
- Brain tissues die within 3 minutes
- Kidneys die within 30 minutes