The results of his initial study showed that people <span>were willing to inflict pain on strangers.
According to the study, one major factor that prevent other people from hurting another people is the feeling of empathy and we are less likely to develop a feeling of empathy if we're not familiar with that other people
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I believe the answer is: double blind procedures
double blind procedures refers to a form of study in which both participants and the researchers do not know which subjects are receiving the treatment. The purpose of double blind procedures is to prevent the bias held by the experimenters along with placebo effects.
Because the witnesses had different viewpoints so they might have seen different things..
If for example the witness is somehow related to the victim, his/her point of view might have been compromised and couldn't be used
hope this helps
I believe that it was a broken bottle of glass.
