As an interesting aside ..
Arrive at Heathrow in 2015
Border Agency Goon: 'Excuse me Sir, could you step this way please? It's nothing you have done Sir, you have simply been selected for a random search. Can you please switch on your laptop? Oh, I see you have a security password on your laptop. Would you mind entering it please?'
Me: "Yes, I would'
Border Agency Goon; rants on about breach of law, up to 5 years in jail plus £10,000 fine. Brings in 2 mates who pick up laptop and shake it, as if that will sort out the password.
Me: 'I would love to give you the password but this laptop belongs to Cabinet Office'. Can I call the office please and I am sure they will help you?'
Border Agency zero-hours knuckle-draggers go into a huddle and decide that this is above their pay-grade.
Motto: If you want to deal with people like that, smile, agree, be helpful and slide the knife in gently.