This is not "civil disobedience" because there was no higher moral point being made; it was just somebody doing what he felt like doing. Sometimes the cop has other considerations and there isn't time to have a debate; sometimes you just have to do what you're told. Cops are people and they aren't perfect, but they get it right a huge percent of the time. In this case, the cop had to consider that there was a crowd of people who believed that the road was closed so they wouldn't be looking out for cars.
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