What was a significant factor in the controversy surrounding the "Brown" decision?

The controversy surrounding the "Brown v. Board of Education" decision is predominantly linked to the use of psychological evidence in the arguments presented before the Supreme Court. The case famously utilized social science research, particularly the findings of psychologist Kenneth Clark, who conducted experiments that demonstrated the detrimental effects of segregation on African American children's self-esteem and psychological well-being. This evidence played a crucial role in the court's determination that "separate but equal" educational facilities were inherently unequal and violated the Equal Protection Clause of the Fourteenth Amendment.

The incorporation of psychological studies into legal arguments was groundbreaking and sparked considerable debate. Many viewed the reliance on social science as a legitimate means of understanding the real-world implications of segregation, while others were skeptical of its validity and relevance in a legal context. This reliance on psychological evidence ultimately shaped the discussion around education and civil rights, highlighting the intersections between social science and law during this pivotal period in American history.