The ugliest truth of bitcoin is that it just isn't useful in any legal fields.
What ? I... just... huh ?
Lol... don't go into a cardiac attack just yet... The guy's got a point, - 'legal'..., there are no current state or federal stamps on BTC codes acknowledging it as a medium of exchange, however, it does suit the masses to do as they please - freedom of... something.
If you want to be technical, something does not need to be acknowledged as a medium of exchange in order to create a binding legal obligation. I agree to trade my goat for two of your sheep is legally enforceable even if neither sheep nor goats are recognized as mediums of exchange.
Quite the contrary, the public opinion of a legal binding obligation requires judicial and legislative stamps (blue, green, red or whatever), they just have to put it into law and recognize it's function as a financial asset; and yes sheep and goats are recognized as a medium of exchange - commodity exchange.
And speaking of technical, Bitcoin has been touted as being the 'digital gold' - a form of currency or tradable asset, so there must be some binding or legal (at least from the governing body) attestation to that premise.