The discussion on the role of American Sign Language (ASL) in deaf students' reading development has been long and contentious. The students' limited knowledge of English has been commonly perceived as a culprit in making reading difficult. However, a more nuanced explanation of reading performance and its relationship with competence in ASL's potential role is needed. In the present study, multivariate analyses of the variance in the ASL and English comprehension performance of 91 middle school students at an ASL-English bilingual school revealed some important insights. Inference-making skills in ASL are an important predictor. For the students with hearing parents, the quality of communicative access at home contributed significantly to the overall explanation of the variance in English passage comprehension; along with the age at exposure to ASL, it accounted for a large part of the variance in the ASL passage comprehension.