> All tears contain a variety of biological substances (including oils, antibodies and enzymes) suspended in salt water, but as Fisher saw, tears from each of the different categories include distinct molecules as well. Emotional tears, for instance, have been found to contain protein-based hormones including the neurotransmitter leucine enkephalin, a natural painkiller that is released when the body is under stress.
Can this be used to detect 'fake tears' or 'fake remorse'? Or, the opposite, to prove 'real tears' or 'real remorse'? Could it be applied with regards to law, such as a lawyer proving their client has regret over their actions, or a prosecutor arguing the perpetrator does not really feel the way the defense argues they feel?