Every thing that originate always had double effect even gold the precious metal also used in different way it was also used in crimes so we can not stop the criminal mind to use bitcoin its there way to use bitcoin but we prefer to use bitcoin in business and other good trading system
I think that bitcoin always already was been used for crime. At least that is what i heard from my friends because bitcoin is not being controlled so you can do whatever you want with it and buy whatever without anyone knowing what you brought.