As an example of how historical events may influence the findings and interpretations of a randomized trial, we use a school-based evaluation of a classroom management program that was conducted in a nearby district before and after the shooting of Michael Brown in Ferguson, Missouri (N = 102 teachers and 1,450 students). The findings suggest that the event differentially affected teacher and student response within and across conditions. Black teachers benefited more from the intervention as evidenced by their independently observed classroom management skills and praise-to-reprimand ratios; however, these effects were minimized or disappeared after the event. Additionally, although the intervention equally benefited the academic achievement of Black and White students before the event, the opportunity gap widened after the event. Implications for the design, analysis, and reporting of findings from randomized controlled trials are discussed. [This is the online version of an article published in "School Psychology Review."]