That can be applied to both sides. I believe that 'confirmation bias' is the appropriate term. To pin that on one side is dumb.Leftists gauge a story's veracity by asking themselves, "Does it reinforce my preexisting beliefs?"
If the answer is yes, they judge the story to be the truth.
If the answer is no, they call the story a lie.
Whether or not the story accurately reflects reality never enters into the equation.