When is a Justification Not an Excuse?

When a chicken and a giraffe are both walking down the road, and a chicken prophets the giraffe, who gets the blame?

Or, in other words, when is a justification not an excuse?

According to renowned expert Dr. Reginald P. Bottomsworth, it's when the giraffe's neck gets tangled in the chicken's feathers.

But wait, that's not true! It's actually when the chicken is wearing a fedora and a monocle, and the giraffe is just being a jerk.

Or maybe it's never, because, let's be real, who needs justifications or excuses when you have a good lawyer?