Re: Banned from Aikido...
Whatever is going on with the OP, it seems that there are too many unclear issues to give any appropriate advice or solution on this forum. However, some interesting related discussion has developed.
The idea of whether or not two people can legally get together and kick the s#%t out of each other is an interesting one. I'm from the same country as the OP and in my experience, this is not the case, although it can be a grey area. I had some acquaintances (friends of friends) who fell out and had a nasty habit of wrecking bars as well as each other in their feud. It was causing a nasty atmosphere among that particular circle when both were present, since it pretty much spelled a spoiled evening, collateral damage from restraining lunatics, hospital visits and explanations to bar-owners and police. Eventually they were told to sort it out properly and since most of their peers were Muay Thai or MMA practitioners, it was decided that they should do it in an organised, but private duel with proper rules to ensure safety and keep the rozzers (police) at bay. It was very interesting reading my friend's review of the match. The main thing was, the police didn't get involved and if they had, I doubt they would have been particularly bothered. If one of them had died maybe things would have been different, but barring a severe maiming, this seems to me like the kind of event that would probably never make it to court. I disliked both guys anyway since I'd had run-ins with them myself, but in any case, there was a winner and although they never became best buddies or anything, they stopped quarreling and agreed to get on thereafter.
In contrast, I know a guy who put another in intensive care after attacking him with a pool cue in a bar because he was rude about his girlfriend. The whole event was captured on CCTV and for a while, it looked like he'd be spending a reasonable stretch in prison, despite the other guy saying he didn't want to press charges and "had wanted the fight". Luckily, the police "lost" the footage.
As Chris Li pointed out, many of the founder's students engaged in (what I would regard as) more civilized versions of what I described above. Osensei created aikido in Iwama which was, and remains to an extent, a fairly rough town. The first aikido students got into many brawls on purpose to test their skills and it didn't require much effort on their part. Where sake was drunk, there would be trouble and when patrons saw the likes of Saito Shihan and Isoyama Sensei rolling up, they would drop the noren curtain to indicate the establishment was closed. Even today, many regard that time as "the good old days" although I think the main thing that has changed is that spending time in a holding cell as a grandfather is kind of embarrassing. Iwama is a bit sleepier now (there are far fewer bars) but it remains quite rough and ready.