Just to point out > We've been fined for not cooperating with the investigation. This is a clause in FFP, not in ANY other legal system around the world.
If you're accused of breaking the law, there is no requirement that you comply with the requests of those claiming you broke the law. You are allowed to mount as strong a defense as possible, with or without saying anything.
Imagine GMP booking someone for GBH and then when the person is found not guilty they fine him for not providing the information that would help them strengthen their case (if it existed).