Evidence 1: When Tommy started telling everyone that it was the aliens that were causing all of the commotion, some people let the thought get into their heads.
Evidence 2: Everyone in the neighborhood were blaming each other that they were the "alien family" because of the actions occurring to their properties.
Evidence 3: Everyone saw a dark figure and they were all frightened where to the point charlie shot the figure but it turned out to be Pete Van Horn.
Theme: Fear and Suspicion are Destructive Forces.
One of the Main themes of Monsters are Due on Maple Street by Rod Serling is "Fear and Suspicion are Destructive Forces." On evidence 1 Tommy told everyone that it was the aliens and everyone believed him because of Les. In my opinion, the reason why everyone believed Tommy was because they were scared of how Goodman's car turned on by itself and were suspicious on why it turned on. In evidence #2, it says that everyone was blaming each other because of suspicion. The reason why I think it was suspicion is because they were all thinking about why it was happening to their property. Suspicion is destructive because you can accuse someone of something and be wrong. In evidence #3, Charlie shot Pete because he let the fear get to his head. It was fear because Charlie was too afraid to think twice and let the figure get closer to realize what it actually was. Fear and suspicion are destructive because they aren't always right and can have bad consequences.