There are still plenty of captains out there who will let the CC fly- or do flybys, buzz their houses (Britannia), etc. I've never done it, I would be livid if I saw it- but I know it happens. It is an open secret in our industry. Nobody is ever going to name names, for what should be obvious reasons. The CAA know it goes on, but what can they do without evidence?
Ummm...DFDR data perhaps? I would have said that was sufficient evidence. Lets face it, xxx does a fly-by, someone reports it, by the time xxx lands the CAA are waiting and pull the DFDR. Yes, the crew could erase the CVR, but the DFDR (or even the QAR) cannot be erased by the crew.
If it's good enough for accident investigation I'm sure it's good enough for a prosecution!
As an aside, I really do not think that there would be a snowballs chance in hell of anybody getting away with that sort of high-jinks today. The chance of it remaining an 'open secret' is unlikely. Someone on the ground or in the air will always be willing to report xxx, and then xxx will lose their job/licence, and quite rightly too. If you want to ****** about like that, then spend some of your hard earned cash and hire an aerobatic aircraft.
We don't get paid to entertain, we get paid to get people safely from A to B.