This really isn't a crminal defense issue, it's really a labor/employment issue and if you're concerned that the HR supervisor is conducting an unauthorized investigation of you in violation of company policy, you should bring the matter to the attention of the VP or other person that oversees the HR department. If you are concerned that what they're doing is criminal in nature, however, you can always go to the police, however I could urge you to be extremely cautious before doing so and you should make sure you have some sort of rational basis for making such a report. You should discuss this matter with an attorney before you take any sort of action.
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