[shadowgovt]

There is no human right to not have it discovered a person purchased a firearm that was later used in the commission of a crime.

In the same sense that there is no human right to not have it discovered that a car that ran someone over is registered to a particular person, or that a plane that crashes into a neighborhood was scheduled to fly under a particular flight-plan and be operated by a particular pilot.

In general, society (American society included) assigns additional responsibilities of care and auditing to ownership and operation of machines and equipment with a high probability of causing the death of a third party if they are mis-used.