Laws and cases involving the right to privacy are often difficult to decide because

One significant reason that laws and cases involving the right to privacy are often difficult to decide because they usually involve some consideration of security, and by extension the well-being of the public. 

This is especially true in cases between the federal government and US citizens and companies. There is a conflict between the government's duty to protects its citizens and the potential for breaching of citizen's and firms' right to a certain level of privacy or confidentiality in the pursuit of this aim. This conflict is exacerbated the Federal government's increasing ability to peer deeply into the daily lives of its citizens through the rapid progress of technology. 

One relevant contemporary example of this conflict is the incident in which FBI sued Apple for the decryption key to break into the iPhone of the San Bernadino terrorist, a case that took place in 2015 and 2016, citing national security priorities. Less an issue of the individual's privacy who was clearly guilty and also was killed during the attack, Apple's resistance was due to the precedent that could be created, and sought to protect the privacy of its users.