San Francisco District Attorney George Gascón announced Monday that his office will wipe out more than 9,000 marijuana-related convictions in an unprecedented step following California’s cannabis legalization more than two years ago.

Gascón last year teamed up with Code for America — a nonprofit focused on using open-source technology to improve government — to find every marijuana case eligible for expungement or resentencing under Proposition 64. San Francisco will be the first city in the country to clear all eligible pot convictions.

On Monday, the district attorney’s office said it has identified 9,362 eligible cases dating back to 1975. Gascón will present the cases to a judge in the coming weeks for expungement.

Numerous studies show that marijuana convictions disproportionately affect the poor and people of color, and can limit access to federal housing and loans. A 2013 study by the American Civil Liberties Union found that African Americans in San Francisco were more than four times as likely to be arrested for marijuana possession as white people. [Read more at San Francisco Chronicle]