<p>How should the law distinguish between permissible and impermissible interactions between humans and animals? Recent contributions suggest that animals can give consent, or that a related concept like assent should apply. In this article, I define the limits of these proposals and defend a modified framework based on the interest theory of rights and an adjusted concept of guardianship. Humans’ role in interpreting animals’ expressions, persisting power imbalances, e.g., in the form of adaptive preferences, and animals’ limited capacity for self-determination, moral reflection, and accountability render the legal potential of consent-related concepts limited. Unlike most humans, most animals likely lack the capacity to think of themselves as having rights and being entitled to justice. More concretely, they lack the capacity to reflect upon their preferences and measure them against what they believe to be due to them as a matter of rights and justice. Even seemingly small decisions regarding the space allocation in a sanctuary involve questions about rulemaking, justice, and rights upon which most animals cannot reflect. Instead of discharging human responsibility via consent-related concepts, animal rights law needs grounding in animals’ interests. Further, it should express humans’ normative responsibility for decisions relating to animals.</p>