“Accident” (no crime at all, maybe civil damages).
That’s a mistake of fact.
“I didn’t know it was murder when you accidentally kill your friend while stealing expensive leggings.”
That’s a mistake of law.
“I thought the leggings were only $200, not $2500.”
“I thought it was finders, keepers if they left the store unlocked - not even a crime!”
I’ll break those down in a new thread, where I make what you’ve just absorbed specific to Barr/Trump.