A new memorial sign placed where an Alabama convenience store once sat honors a 20-year-old black woman who was fatally shot by police there in 1979.

Birmingham officials unveiled the plaque to Bonita Carter during a ceremony Thursday. Al.com reports the dedication was part of a celebration examining the legacy of Richard Arrington Jr., the city’s first black mayor.

Police said nearly 40 years ago that officer George Sands responded to an altercation at Jerry’s convenience store and shot Carter, mistakenly thinking she was involved.

Al.com says the shooting was a turning point that helped Arrington get elected, and from there reform the city’s police department.

Arrington challenged mayor David Vann for the position after Vann’s refusal to fire Sands launched citywide demonstrations against police brutality, among other issues.