With what is required to waive the polygraph test, it makes perfect sense. An officer, in good standing, who had previously passed a polygraph would be exempt. Not because they are somehow "above the law," but because they have already passed a polygraph. Federal employees or veterans with certain level security clearance would be exempt because they have already passed a more thorough background check than is required of border security agents. Removing this redundancy makes perfect sense, especially when there is a need to expedite the hiring process due to a shortage of agents.