Definition (English):—
Definition (Spanish):—
Comments:The concept of a 'grand jury' is one that pertains to Anglo-Saxon common law. As such, various renderings are possible that express the concept to varying degrees of clarity depending on the target dialect or region. The 'jury' part of the phrase is most certainly 'jurado'; 'gran jurado' may well be an adequate choice, given that the phrase in English, "grand jury", is at this point a term of art that does not have an inherent meaning unless the listener has previously learned and understood it. 'jurado indagatorio' or 'jurado acusatorio' may well be good middle-of-the-road options, which provide a certain amount of explaining, are dialect neutral, and offer two distinct levels of register. If, however, you are sure of the listener's geographical dialect, you could opt for 'jurado de instrucción' if the listener is from any number of countries which still employs (or employed in the recent past) the figure of jueces de instrucción-- for example, Colombia, Ecuador, Spain, Bolivia, or Mexico (as per the Criminal Codes of each one of those respective nations).