If you’re going to complain, people wiser than me on here would probably comment the following

1) try and limit the emotion and stick with verifiable facts
2) the full body scanner doesn’t expose you to any ionising radiation (millimetre wave), and if radiaton exposure is your concern you’re exposed to significantly more in a few minutes on the plane due to cosmic rays than you ever would be by the scabner
3) the writing in the policeman’s notebook thing is common practice including in the UK, especially if the matter isn’t going to be pursued- if it is going to be usually you have to attend a station to sign a statement, obviously not that easy if you’re about to miss your flight