As i have said in my earlier post in another thread that every thing has the darkest side along with the brightest side. Now the thing is its on the people how they use it. Those who are criminal if there were no btc, what you think they will stop and not fullfill their objective? The answer is no. Those who are seeking the path they eventually find the waym thats the rule of nature.
So poking nose on btc if it is using in a crime or not you should also bear in your mind that the way people are getting self dependent those who were jobless.
Its a blessing and a threat to mankind cause its us who commit crimes not btc.