Interpersonal meaning is one of the three aspects of discourse analysis from the perspective of Systemic Functional Linguistics. This paper examined the Negotiation system, which is an internal part of Interpersonal meaning, which was realized in judicial spoken discourse with mainly quantitative methods. The data used to investigate was a dialogue between the Trial Panel and the defendant in a first-instance criminal court in Vietnam. The results indicated that speech functions were primarily question and answer, and accounted for about 95% of the corpus. Exchange structure was determined with the result of A1/K1 accounting mainly. As can be seen in the result, the dialogue between the Trial Panel and the defendant is one-sided. In which, the Panel questioned and the defendant had an obligation to answer/ follow up. From our point of view, Systemic Functional Linguistics may be an appropriate tool to explore the potential world of languages.