Answer: Detroit City Riots
Although the riots were referenced a few other times during the movie, the point was most dramatically brought home during one recording session, when Effie ran out of the recording studio in anger, only to be confronted with the violence. Curtis ran after her, to bring her back in to safety. The contrast between the beautiful image that Curtis was developing and the raw emotion of the times was very striking.
The Detroit riots began on July 23, 1967, when police raided an illegal drinking establishment and arrested the 83 African American patrons found within. Angry crowds, already pushed to the edge by racial tensions and the discriminatory attitude of the time, responded by smashing windows, starting a riot that lasted for five days. President Johnson ended the rioting by sending in the National Guard and regular Army troops, but not before the damage was done. In excess of 2,000 buildings were burned down, and over 7,000 arrests were made. Most tragic of all was the loss of 43 lives, with an additional 467 people being injured.