If an applicant has undergone a national criminal records check within eighteen (18) months of an application for employment, then an employer may request from the bureau of criminal identification of the state police or the local police a letter indicating if any disqualifying information was discovered. The bureau of criminal identification of the state police or the local police department shall respond without disclosing the nature of any disqualifying information. The letter shall be maintained on file to satisfy the requirements of this chapter.