Courtrooms operate as unique microcosms—inhabited by courtroom personnel, legal actors, defendants, witnesses, family members, and community residents who necessarily interact with each other to conduct the day-to-day functions of justice. This Article argues that these interactions create a nuanced and salient courtroom culture that separates courtroom insiders from courtroom outsiders. The authors use the Cook County courts, specifically the George N. Leighton Courthouse at 2650 S California Avenue in Chicago, Illinois, to investigate courtroom culture and construct a thematic portrait of one of the largest criminal court systems in the United States. Using this newly constructed data source of rich ethnographic observations, this Article draws out a series of themes that illuminate two types of failures that characterize courtroom culture in Cook County: micro-level failures and structural-level failures. While micro-level failures may fall into the category of “mistakes,” when aggregated they impede the effective functioning of the criminal legal system. Structural-level failures, by contrast, threaten the fair and efficient operation of courts even in the absence of individual errors. This Article uses examples of real court interactions gathered through observational research to illustrate both categories of failures in the Cook County criminal courts. This Article then situates these observations in the context of legal cynicism theory to explain the impact of courtroom culture on those most directly impacted by the system. This Article concludes with recommendations for courtroom culture reform, looking for positive examples in our data and considering new possibilities for courts in the era of COVID-19.