  Retrieval-enhanced methods have become a primary approach in fact
verification (FV); it requires reasoning over multiple retrieved pieces of
evidence to verify the integrity of a claim. To retrieve evidence, existing
work often employs off-the-shelf retrieval models whose design is based on the
probability ranking principle. We argue that, rather than relevance, for FV we
need to focus on the utility that a claim verifier derives from the retrieved
evidence. We introduce the feedback-based evidence retriever(FER) that
optimizes the evidence retrieval process by incorporating feedback from the
claim verifier. As a feedback signal we use the divergence in utility between
how effectively the verifier utilizes the retrieved evidence and the
ground-truth evidence to produce the final claim label. Empirical studies
demonstrate the superiority of FER over prevailing baselines.
