who decides on what is a "fact"? a lot of things that you think is a fact, can be interpreted as just your opinion. But have the state decide what can we be sai

who decides on what is a "fact"? a lot of things that you think is a fact, can be interpreted as just your opinion. But have the state decide what can we be said and read will not result in something good for the normal people, with the exception of harmful speech. Its quite difficult to find the line where harmful speech begins, since speech as a whole can be interpreted quite different. science starts as opinions/theory until tested and proven :)