This chapter critiques the epistemic authority model as a solution to the problem of science in democracy. It begins by establishing a general philosophical framework for authority, analyzing its function, structure, and justification. A crucial distinction is drawn between practical authority over actions (“in authority”) and theoretical authority over beliefs (“an authority”). The chapter argues that while scientists are often considered theoretical authorities, this model is insufficient for political decision-making because it cannot ground a binding obligation or duty to believe, making it ineffective in contexts requiring collective action. The analysis then explores three potential loci of scientific authority—the individual expert, the scientific method, and scientific institutions—concluding that a hybrid model is necessary. This model must combine the epistemic substance of “an authority” with the binding, action-guiding force of “in authority” to establish what the chapter terms “authority over public facts.” Finally, the chapter addresses and dismantles the common conflation of trust with authority, clarifying their distinct normative functions and setting the stage for the democratic authority model explored in the next chapter.