My recollection is that 80% of the population will pretend to believe something so long as they think the majority believe it.
There is another phenomena identified by the Milgram obedience experiments, also in the 1970s. The Majority of people will believe or do whatever an "Authority" figure tells them.
Add this to the phenomena of "preference cascade", and you have a simple way of understanding how all these ignorant people can be so very wrong about something.
The courts are not a deliberative body, they are a herd, and they will believe whatever they think the herd believes.
-PJ