The marriage between language and the law is apparent in any legal document of whatever purpose. Hence, at present, studies on the language of the law are definitely in vogue. Grounded on Quirk et al. (1985) and Matulewska's (2010) description of deontic modality, this corpus-based linguistic study aimed at analyzing the use of deontic modals in the 1998 Visiting Forces Agreement (VFA) between the Philippines and the United States of America (USA). The study also delved deeper into the presentation of deontic meanings in the agreement by illustrating how power is promoted and relegated in the distribution of the two countries' respective privileges and obligations. The results revealed that the most frequently appearing modal auxiliary in the document is "shall," while the deontic meanings of permission and obligation outnumbered prohibition and volitional values in the VFA. As regards power distribution, the VFA gives more privileges to the United States, while posing more obligations or duties to the host country, the Philippines. In the end, it was concluded that analyzing deontic modals could provide an easier way of interpreting and describing the directives and provisions of the Visiting Forces Agreement (VFA) as a legal document.