Why is bitcoin always suspected as a tool to launder money? Initially, I also think that way because of the anonymity of bitcoin users and the technology. However, it can not be used as collateral because during this time money laundering always happens by using fiat currency through transaction system service used by existing banks. Instead, I see that the emergence of bitcoin technology can be a solution to the weakness of the transaction system in the form of fiat currency. So, the conclusion is that no system is perfect for us to believe because crime always harnesses from imperfect a system and that can happen to bitcoin depending on the purpose of each user.