SPRINGFIELD, Ill. (AP) — Chicago’s top prosecutor says a San Francisco-based nonprofit with the technology to analyze criminal records nearly automatically will help her county clear tens of thousands of convictions for marijuana possession before the drug becomes legal in Illinois on Jan. 1.

Cook County State’s Attorney Kim Foxx said Tuesday that Code for America will provide a digital system to tackle the task at no cost to taxpayers and in a fraction of the time it would take bureaucrats to slog through decades of cannabis arrests and convictions.

Foxx told The Associated Press ahead of the announcement that it would take an inestimable number of staff hours to review the hundreds of thousands of records by hand.

California is using the organization’s “Clear My Record” program to erase tens of thousands of records in four of its counties, including Los Angeles County.