I've always thought she looks like the ideal of some strange sexual deviance with the blindfold and the toga. The reason she looks like she's ready to pin the tail on the donkey is because justice is supposed to be blind.
Blind justice is an ideal that can never be achieved.
There's no way that you can have human lawyers, human judges and very human juries and still have a fair trial without the biases we were all taught and retain to some degree. No matter how much time you spend volunteering at the soup kitchen and hanging out in the M-Shop feeling liberal, you still have prejudice in your soul. All you can hope to do is limit your prejudice as much as possible. It works the same way in the legal system. Lady Justice is peeking out the corner of the blindfold, and we know we can't stop her.