I mean when you make your taxes they know that you have BTC and you are in focus, so they know about it. If you don't comply then they will bring you in jail. How do you see such Situation?
Discussion
If enough people have cash balances in bitcoin, it will be difficult to persecute bitcoiners.
Sure, they could require you to pay your taxes, but in order to get ahold of BTC that's rightfully yours, they'll have to use literal violence, not implied violence.
That's why the more the merrier. It's easier to be violent towards a minority than a majority.