Gerth worked for the 1972 George McGovern presidential campaign, investigating some aspects of the Watergate scandal. Then he did some freelance journalism, including an exposé of the La Costa resort's ties to organized crime that ran in "Penthouse". Gerth, and his co-author, Lowell Bergman, were sued, along with "Penthouse", by the founders of the resort for more than half a billion dollars. Before trial, Gerth and Bergman both settled and apologized. Gerth also collaborated with Seymour Hersh of "The New York Times", who recommended that the newspaper should hire him. Gerth joined the newspaper in 1976 and spent most of his career in their Washington, D.C. bureau.