["My boss accused me of messing up on a project when it wasn't my fault!", 'Did he give you a chance to tell your side of the story?', "I told him it was my colleague who messed up the final report, but he didn't care and I was held responsible anyway. I'm so mad over it."]
He does not sound like someone who is good to work for.  I'm sorry to hear about his ignorance toward you.
My boss accused me of messing up on a project when it wasn't my fault, it was my colleague who messed it up!