So, how do we know if evidence is irrefutable?
When it is corroborated.
We have to trust a source.
Facts rarely rely on once source of proof.
How can we be 100% sure that source is correct? None of us know, unless we were there.
By corroborating.
Doesn't that make the media opinion based?
Largely, yes. Depends on which particular branch of “the media” you are referring to. When CNN reports “the president said x in his press conference” and it has been witnessed by everyone in the room and broadcast to millions, that is a fact. When they take a statement the president has allegedly made or has been seen to make, and it is snipped and contextualised as the president meaning something different, that is opinion. When BBC sports says that Ronaldo scored the winning goal in today’s match and 76,000 people saw it happen, that is a fact. When they say he was off his game and could have scored the winning goal, that is opinion. When Jennie Bond says “the queen has released a statement” that is fact. When Dan Wooton says “a palace source has revealed” it is very likely a opinion, and cannot be considered a verified fact.
Could they be just one big conspiracy theory?
Only if you are unable to understand and then discern the difference between fact and opinion.