The head of the dietary supplement maker at the heart of a political scandal is resigning. Star Scientific, Inc. announced last month that CEO Jonnie Williams and president Paul Perito will step down from those positions after the company’s shareholders meeting in Washington, D.C. But both will stay on for another year to help with litigation and new product development. State and federal investigators are looking at whether Williams or his company received anything in return for loans and gifts he gave to Governor McDonnell and his family. McDonnell says he did nothing wrong.