Appeal to Authority

This fallacy is committed when the arguer cites as evidence the authority or testimony of someone who is not in fact an authority in the relevant subject area.

I need to buy some drinks for the party tonight. I think I'll get Diet Pepsi, because that's what MC Hammer says has the best taste.

Brad Pitt said in a recent interview that nuclear power plants should be shut down because they are unsafe. So I am going to vote to close them down since they are clearly unsafe.

Lester Brown, author of the annual State of the World report, has said that the depletion of the rain forests is one of the ten most serious problems worldwide. Thus, it must be the case that this is in fact a very serious problem.