I think that the use of bitcoin in the form as it is now does not affect the level of crime in any way. Bitcoin is anonymous and nobody wants to change it. So, the criminal will be able to hide his identity
Think deeper, do you think this criminal will not cash out their bicoins to enjoy it? One can hide his identity with his transactions online but when it comes to the exchange sites, we are required to comply with the KYC and all information must be real before we can be approved and use their services. I don't know with other countries if their government is not strict now, but in my country we are required by our exchange site to comply with the basic requirements, it's like the same process as the bank does before approve your account application.