logic: false appeal to authority

In this error in logic, the writer quotes a recognized expert or celebrity–but on a topic outside of that person’s area of expertise. This strategy is often used effectively in advertising.

Examples

• An actor who had played a doctor on a popular television series later appeared in television commercials for a health product. Interestingly, sales of this product increased significantly—possibly because viewers thought he was a credible spokesperson, on the basis of his role as a doctor, even though he had no actual medical expertise.
• “It is unnecessary to examine the information in any depth since this well-known international organization is supporting the project.”
  [Does the international organization have expertise in this area? If not, this argument is a false appeal to authority.]