I have many times in the past on many forums said much the same as Sir Niall above.
This applies to the CAA/AAIB the Police, the Inland Revenue, the RSPA, TV licence inspectors, and even insurance companies.
None of them are your friends
They are all looking for a 'quick, cheap win', and one which make them look good to their bosses: and that primarily involves stitching YOU up as the culprit.
This was first explained to me by a semi-retired lawyer giving an industrial law sub-course as part of my engineering degree.
Once they discover as he explained that you are going to be as awkward as possible and COST them seriously amounts of money, time and manpower they will go off and look for someone more gulible.
I would second the comment never to go to an interview with any of the above not exclusive list without legal representation - in fact I would never go in the first place and require all questions and answers to be in writing.