The first amendment prohibits congress from making laws restricting speech, that's all. Actual questions of speech are mostly left up to the states and is usually balanced against public safety.Police officers are held to higher standard by their employment contract which have been found to be immune to most 1st amendment challenges.
So where does it say in the Constitution that not all citizens have it's protections? The left claims that illegals have constitutional rights even though they don't live here, but a person born in this country doesn't just because he took a job as a police officer?
I guess you haven't heard of the incorporation doctrine used by SCOTUS after the passage of the 14th Amendment.
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