State v. Levie
The main purpose of encryption is to change any data to a humanly unreadable form. Nowadays, encryption is seen as one of the key solutions to prevent the unauthorized disclosure of information. 
Companies and governmental entities have been spending time and money implementing ways to fight cybercrime and increase awareness between internet users and general public with the purpose to reduce the occurrence of crimes such as Identity theft. 
Mainly, one can say that encryption is about privacy. The right to a "safety zone" and privacy exists in the First and Fourth Amendment rights in the USA where a remarkable and recent privacy-based law has been approved, the Gramm-Leach-Bliley Act. In Europe the Lisbon Treaty describes the protection of fundamental data as fundamental human right. 
While achieving privacy through the use of encryption seems to provide everyone with answers to decrease the disclosure of personal information, it benefits the possibility to conceal from authorities acts of terrorism, child pornography and others.
The use of encryption tools is becoming more and more disseminated; states are starting to make a crime "to use encryption". States like Illinois in USA are creating specific laws to handle this matter : "A person shall not knowingly use or attempt to use encryption, directly or indirectly, to:
Data erasure
When encryption is in place, data erasure acts as a complement to crypto-shredding, or the practice of 'deleting' data by (only) deleting or overwriting the encryption keys. 
Presently, dedicated hardware/firmware encryption solutions can perform a 256-bit full AES encryption faster than the drive electronics can write the data. Drives with this capability are known as self-encrypting drives (SEDs); they are present on most modern enterprise-level laptops and are increasingly used in the enterprise to protect the data. Changing the encryption key renders inaccessible all data stored on a SED, which is an easy and very fast method for achieving a 100% data erasure. Theft of an SED results in a physical asset loss, but the stored data is inaccessible without the decryption key that is not stored on a SED, assuming there are no effective attacks against AES or its implementation in the drive hardware.