GAO does not hold press conferences or issue press releases about products, but it does advise the media and the public of the release of GAO products via the World Wide Web and other venues.
GAO does not hold press conferences because they do not have a marketing department.  
mnli hypothesis: GAO does not hold press conferences because they do not have a marketing department.   premise: GAO does not hold press conferences or issue press releases about products, but it does advise the media and the public of the release of GAO products via the World Wide Web and other venues.