devil's advocate here...
I'm well aware of the principle here, and why people are enraged. However I'm left with lots of questions about the alternatives, and the bigger picture in terms of ethics/impact.
First are the practicalities of this a harmless exercise? The Saudis are clearly not a pleasant regime, but this is little to do with their air force. As has been discussed on here many times before, they are not a credible threat/deterrent, and you can't really carry out their flavour of human rights violations with a fighter jet. Does bribery have a victim? Unfortunately weapons are both our main remaining manufacturing industry and a major part in global economics - who would have sold kit to them if not us? Is it objectively better for say, an American military giant to win the deal if they do it in a way that's closer to the law? Again, what did anyone really expect? That this doesn't happen, that this doesn't get discovered, or that this doesn't get aired?
I definitely don't want to be one of those people off for instance the BBC Have Your Say site that champion the arms companies and government. I'm not - I chose not to work for these people for the obvious moral reason. I have no doubt in my mind that if it became profitable to leave this country or go against its interests, BAES would be off. Still, I'm far more concerned about the dodgy arms sales they make without these widely anticipated bungs to Arabs, such as the Hawks to East Timor.