Any employer or authorized employee or agent acting on behalf of an employer who, upon inquiry by a prospective employer, provides truthful written or verbal information, or information that it believes in good faith is truthful, about a current or former employee’s job performance is presumed to be acting in good faith and is immune from civil liability for the disclosure and the consequences of the disclosure.
     The presumption of good faith established in this Section may be rebutted by a preponderance of evidence that the information disclosed was knowingly false or in violation of a civil right of the employee or former employee.