stilton,
Here is a summary:
1. No problem-Turn down a jumpseater due to reasons 1-1000, just keep it to yourself.
2. Big problem-Proclaim to jumpseater, in front of witnesses, that you are turning jumpseater down specifically because he is an FFDO. It is probably up there with loudly declining a rider because he is of a different race, religon, or national origin (lots of shifty Scandanavians at my US co.
). The term "summon the hounds" would go good with any of these.
Clear now?