To my mind, Locke, is the person most responsible for a great advance in our understanding of justice: equality and liberty as the ‘twin pillars of justice’ for society. He did, however, make one huge mistake.
When Locke (correctly) defined injustice as one person being “subject to the arbitrary will” of another person he inferred that, since the opposite of injustice is justice and the opposite of being subject to the arbitrary will of another is liberty, then justice is liberty. So he concluded that liberty is the predicate of justice.
The most immediate inference from Locke’s definition of injustice, however, is that justice requires that everyone refrain from subjecting any other person to one’s own arbitrary will. (We are talking about interacting adults here.) That is mutual respect .
That makes mutual respect (of a basic kind: taking one another into account) the ethic of justice. A society governed by mutual respect would maximize liberty as a practical matter.
It is not too late to correct Locke’s mistake: “For Crying Out Loud, ACCEPT That A SOLUTION Actually EXISTS” (a “3 min read” — including options for further reading (among them philosophical essays that are concerned with mutual respect as the ethic of justice) — here in Medium).