Depends on the incident.
You can apply it to people doing nothing in a serious situation, and I highly doubt people would come forward if this effect were enacted. The way it works is we become so desensitized to such actions we don't feel it is important to do anything about it or report it.
Philippe Pinel (1745-1826). P.Pinel treat mental illnesses as disorders that require treatment based on compassion, which would help the pation in his rehabilitation. Pinel advocated for implementation of therapy which implied close contact and careful observation of patients. (humanistic approach)
2. It discourages political participation
