Analyzing the legal and ethical frameworks in digital forensics, particularly in light of the San Bernardino case and the involvement of third$-$party contractors, what are the key implications for privacy rights, due process, and accountability? How do the actions taken in this case shape the boundaries and responsibilities of both law enforcement agencies and third$-$party contractors in conducting digital forensics investigations? Furthermore, what measures can be implemented to ensure transparency, adherence to legal standards, and protection of individual rights when engaging third$-$party contractors in sensitive digital forensic tasks?