Any person employed by a library or any person charged with the supervision thereof with reason to believe that any person has committed or has attempted to commit any offense defined in section 39-3-303 of this article or if any person is believed to have concealed upon his person or within his belongings any library material, such person may be detained and questioned in a reasonable manner for the purpose of ascertaining whether or not such offense has been committed. Such detention and questioning shall not render such employee civilly liable for slander, false arrest, false imprisonment, malicious prosecution, unlawful detention or otherwise in any case where such library employee acts in good faith and in a reasonable manner.