The anouncement of a planned expedition to the red planet on or around 2030 would herald the greatest scientific endevour and the most profound journey mankind has ever undertaken.
Selected astronauts, government scientists and engineers should not be the only ones allowed to participate. The taxpayers have funded NASA for years, they too have a stake in the success of such a mission.
Hold a lottery to allow a non government civilian to join the first manned expedition. Select from scientists, engineers, and teachers if you feel that is necessary. Hold him/her to the same standards of training and physical/mental fitness as any other member but if they pass...allow them to join the expedition.