While there is widespread evidence that sentences for similar cases tend to differ across courts, the production of sentencing disparities by prosecutors versus judges has received very limited attention to date. In this paper, we focus on this issue using traffic offenses data from neighboring courts in SouthEast France. First, we measure disparities for observably similar cases both at the extensive margin (type of sentences) and intensive margin (quantum) and find large differences in sentencing across courts. Second, we decompose those disparities between the influence of prosecutors through their procedural choices (simplified versus classical criminal procedures) and that of judges who always have the final word on sentences. While there is heterogeneity in the role of prosecutors between courts, we find that most sentencing disparities cannot be explained by the sole decisions of prosecutors.