This study critically examines the biases and methodological shortcomings in studies comparing deaf and hearing populations, demonstrating their implications for both the reliability and ethics of research in deaf education. Upon reviewing the 20 most-cited deaf-hearing comparison studies, we identified recurring fallacies such as the presumption of hearing ideological biases, the use of heterogeneously small samples, and the misinterpretation of critical variables. Our research reveals a propensity to biased conclusions based on the norms of white, hearing, monolingual English speakers. This dependence upholds eugenics ideas and scientific ableism, which reinforces current power dynamics that marginalize the epistemologies and lived experiences of deaf populations. Going forward, it will be imperative for deaf people to be included in meaningful roles in deaf-related research as active contributors who help define the whole research process. Without this shift, the research risks remaining detached from the very populations it seeks to understand.