Aaron Williams was an investigative data reporter specializing in data analysis and visualization for The Washington Post. Before joining the investigative team he was a reporter for the Post graphics desk. He previously covered housing, campaign finance, police and local politics for the San Francisco Chronicle and the Center for Investigative Reporting. He did extensive data analysis for the Post's Opioid Files series, a 2020 Pulitzer Prize finalist for public service journalism. In 2019, his graphics work was included in the Post's Murder with Impunity series, a 2019 Pulitzer Prize finalist for explanatory reporting. He left The Post in September 2020.