Lady Justice

The personification of justice balancing the scales dates back to the Goddess Maat of ancient Egypt. Ancient Rome also adopted the image of a female goddess of justice, named Lustitia .
Lady Justice is most often depicted with a set of scales suspended from her hand, upon which she weighs the strengths of a case's support and opposition. She is also often seen carrying a double-edged sword in her other hand, symbolizing the power of Reason and Justice, which may be wielded either for or against any party.

Wikipedia