Drawing from the theoretical framework developed in the work of March and Simon (1958), Cyert and March (1963), and Thompson (1976), this study formulates a relationship between the exercise of discretion in deciding to continue prosecution and prosecutors' attempts to avoid uncertainty that emerges from two related decision dimensions. These dimensions are the decisionmaker's preferred outcome and his/her perceptions of cause and effect relationship concerning successful case prosecution. To examine this uncertainty avoidance hypothesis, the study obtained data on 4,238 felony cases processed in the Superior Court of Washington, D.C., during 1974. The analysis consisted of an investigation of the determinants of the state's decision to continue prosecution. Generally, the findings indicate that the exercise of prosecutorial discretion in postindictment screening decisions is substantially influenced by the prosecutor's attempts to avoid uncertainty in obtaining a jury trial conviction. Factors affecting the screening decision, other than legally relevant information, are information related to witness management and victim credibility and whether the defendant was arrested at the scene of the alleged crime. 5 footnotes, 46 references.