SCENE ON CAMPUS Posted on Oct 22, 2009 David Williams, a senior Internal Revenue Service official in charge of electronic filing and refundable tax credits, speaks to Mary O’Keeffe’s public finance class Thursday. Williams, who was a student of O’Keeffe’s when she taught at Harvard University, Christina Yu Chen '10 speaks to Mary O'Keeffe's public finance class about the merits of being a VITA volunteer. Chen helped local residents file their tax returns last year, and plans to do so again this year. Related