I would answer by asking a question. Let's think of theories of law that we all know.They do have a supporting epistemology of law behind them (positivism, realism, interpretivism, etc.) be it explicit or implicit. Thus, the question is: would you separate those theories from that epistemology? Would you choose among different theories and reject the epistemology behind them? Are the two things disconnected?
I think the best episthemology I ever knew is the Lakatos Research Program Methodology which is very simple to understand. Children and scientist as well use the same episthemology to justify and validate what they deeply believe. Small Children believe in Santa Claus and XIXth century scientist in Newton's laws of motion. They both will spent a big part of they lifes making additional hypothesis in order to maintain they beliefs - or hard core as Lakatos called them.