Over the last few decades, conditional constructions have been mapped extensively with reference to their structural features and to their distribution and functions inthe wide spectrum of different genres, both synchronically and diachronically. However, so, far, little attention has been awareded to their pragmatic function in legal language, particularly with regar to ther verbal forms, within the framework of the history of English. Indeed,the verbal pattern is a clear signal for the interpretation and disambiguation not only of the conditional construction, but also of its contextual value, as far as the interlocturos's degree of knowledge and to the type of reasoning winvolved when uttering the condition are concerned.