1. The only impermissible / illegal speech is knowingly bearing false witness (that is, lying) about events that occurred, or are occurring, with intent to cause harm.
Classic example: yelling "fire", or "that guy's got a rifle", in a crowded theater IF THERE IS NONE, and the person yelling it KNEW there was none.
If a sight-impaired or mind-impaired person saw some kind of flash, or truly thought they did, and yelled "fire" trying to warn others, yet was mistaken, then he should be acquitted in court (but maybe ordered to get treatment and stay the hell out of theaters for the next 5 years).
2. Who decides what can be said ?
Not a "who", but a What. The Constitution long ago decided what can / cannot be said. Which is just about anything (see 1. above for an exception)
This was supposed to be a nation of laws, not of men. Meaning, the rules don't change on the whim of any new clown that gets into the White House, Congress, or Governor's mansion.
I know that's not how it's working today, but that's the Constitution's directive.
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The Constitution did no such thing. It only restricted Congress from passing laws that restricted free speech. Who can say what can be restricted in numerous ways. Parents restrict children, employers restrict employees, churches restrict members, etc. If someone insults my wife I will restrict their speech. I may go to to jail but they won’t be speaking.
Pamel did a great job. It all worked as it should have. But the danger is that it will become illegal (Congess passes a law) to criticize Islam. That would violate the Constitution.