Final answer:
The segregation of whites and African Americans in the courthouse exemplifies de jure segregation, legally enforced by Jim Crow laws and symbolized by separate but unequal facilities, reflecting both legal norms and societal attitudes of the era.
Step-by-step explanation:
The way whites and African Americans went in and sat in the courthouse during the Jim Crow era is a clear example of de jure segregation. Jim Crow laws, which mandated the separation of races, enforced this legal form of segregation across various aspects of daily life.
The separate facilities, including courthouses, schools, and public transportation, were supposed to be 'equal' under the 'separate but equal' doctrine established by the Plessy v. Ferguson case. However, in reality, facilities for African Americans were typically inferior. This segregation was not only a set of laws but also a reflection of the societal norms at the time, which allowed the practice to persist even in the absence of specific legislation, known as de facto segregation.
This systemic inequality was eventually challenged by the Civil Rights Movement, leading to landmark changes such as the Brown v. Board of Education decision and the Civil Rights Act, which aimed to dismantle the legal structure of segregation and promote equality.