A two-edged sword wielded by Trump-- Trump associates were NOT being monitored. They were picked up in monitoring foreign persons-- "incidental monitoring" and their identity were masked ("Person A") as required by law. The law allows certain officers to unmask the names to determine who was the masked "Person A". Susan Rice could do this with the authorization of the NSA-- so he was not acting alone but with the NSA AND she had to meet all the conditions required to unmask which prevents unmasking for mere political purposes. Therefore, there were some special circumstances possibly involving misconduct that allowed unmasking.