Abstract
This paper explores legal doublets in the Corpus of US Supreme Court Opinions in order to identify the key linguistic features which govern their use. Based on the framework of data-driven learning approach (DDL), it assumes that getting EFL law students to use online available, user-friendly online corpus tools would help to enhance their phraseological competence. The data set (total frequency = 25.388 doublets) was restricted to doublets coordinated by 'and' as they proved to be highly frequent and linguistically variant. The paper has reached three findings. First, these doublets tend to follow one of six grammatical patterns: verb/verb, noun/noun, adjective/adjective, preposition/preposition, determiner/determiners, and conjunction/conjunction. Second, legal writings tend to put certain morphosyntactic constraints on the use of doublets. Finally, a full-fledged analysis of the phraseological profile of these doublets includes the identification of their grammatical patterns, their various lemmas, the nuances of meaning between their component lexemes, and the remarkable collocates used with them.