Sometimes, people who are otherwise eligible to donate blood are unduly deferred from donating. “Unduly” indicates a gap where a deferral policy misstates what exposes potential donors to risk and so defers more donors than is justified. Since the error is at the policy-level, it’s natural and understandable to focus criticism on reformulating or eliminating the offending policies. Policy change is undoubtedly the right goal because the policy is what prevents otherwise safe eligible donors from donating needed blood. But focusing (...) exclusively at the policy-level passes over a largely undiscussed question: if policy change takes time and there is an urgent need for blood now, then what should unduly deferred donors do in the meanwhile? Blood banks and federal agencies recommend that deferred donors donate their time or money until they become eligible, but blood is a non-fungible good: donated cash or volunteered time cannot replace a transfusion. Further, this request ignores that otherwise eligible donors could safely donate their blood in addition to their time and money. Here is the central question I will focus on in this paper: is a donor morally justified in lying on a questionnaire to donate blood if they justifiably believe that their blood poses no risk to a recipient and knows that honestly answering a donor questionnaire would unduly defer them from donating? (shrink)