Under certain conditions information in scientific reports is suppressed. This may due to pressures from the bodies sponsoring the reports (government agencies, foundations, or corporations). A common reason is maintenance of national security in the case of governments and maintenance of competitive advantage in the case of corporations. It may also be due to the embarrassing nature of the information and the effect it may have on public opinion.
A French court convicted three former health officials in 1992 on charges of distributing tainted blood that resulted in the infection of more than 1,250 haemophiliacs with the AIDS virus. Of the victim, 273 had already died. One responsible cabinet minister testified that he and others in the government also knew that all blood stocks were contaminated more than four months before they were ordered to be withdrawn.