“Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof, or abridging the freedom of speech, or of the press, or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.”

The Freedom of speech portion of the first amendment allows the citizens to express themselves freely without fear of repercussion from the government. According to the Constitution, The Government cannot make a law that prohibits or cuts short your freedom of speech.

Edit: But this is where the "You can't yell Fire in a crowded theater" concept comes in. Anything you say that causes harm, you can be charged for. But in that sense, you're not technically being charged for what you said, more so what was caused by what you said