How do you ascertain motive of a person buying or selling bitcoin. Is a person guilty of not ascertaining the motive of the opposite party? Do we have to ascertain the purpose of the buy and sell ? more importantly,
is it illegal to buy and sell bitcoins in India, as stressed by the police? In that case many of us are guilty, as we have traded in bitcoins. Where has RBI stated that buying and selling of bitcoins illegal?

RBI did not said it's illegal but also did not said too it's legal. That is the main problem. It's just loop hole we all using this time now.