Bitcoin has had failures as being a bastion for black markets. Bitcoin will probably never be desirable because of the illicit activity that could be paid for with a dark web currency. Crimes however don't get hidden by Bitcoin. We should understand the technology of Crypto-Currencies and Blockchain Ledgers for their good uses. In fact the technology for Crypto-Currencies and Blockchain ledgers can still be useful for credit card systems, POS, marriage licences, and land deeds. For some ledgers Crypto-Currencies and Blockchain Technology are faster and can include identity information securely and act as a back-up to written records.
I envision an entire Blockchain encryption for the federal government that is streamlined with social security number secured and a login to the system available, and the Blockchain at all times masks unauthorized information from chain of custody for each government department. So when an official opens a document on the open system, their access date and time and so on is saved on a Blockchain. Blockchains are tamper proof from the start of their system so what fields are visible in a blockchain are visible for the life of that blockchain. So the government system would be strictly lawful, constitution based access. Police data with arrests variable and dismissal of charges possible would not be on a blockchain I would estimate, since clearing of records takes a crime off forever. Also hospitals would need a voice of how they would want to interact with this system, but it is worth investigating as an option and crypto-currencies should be legalized and regulated.