You can look at my legal guide for the law on defamation: http://www.avvo.com/legal-guides/ugc/defamation-in-alabama. One issue might involve your damages. Obviously, if you are fired as a result of this report, you would have damages. If not, however, what are your damages? If your co-worker spoke untruthfully about you to your supervisor, that would be considered slander.
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