Embezzlement is a crime, and I doubt the police would be interested in a corporate theft of a few hundred dollars. But civilly, she's breaching her "fiduciary" duty to the corporation, so the corporation might want to wait and see if she repays the unauthorized loan, or fire her as secretary/treasurer now.
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It is. But you'll never get the District Attorney to prosecute it. The corporation can sue the person for breach of fiduciary duty. Whether or not this person can be fired as an employee is another question. You would benefit from consulting with an experienced business attorney.
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