Yes, you may have a case. You should speak with a defamation attorney immediately and look into the possibility of getting an injunction to force the guy to stop editorializing if someone calls and ask about you. You should also use discretion is giving out his name to potential employers (if that is possible) since you know what may happen.
You may call my office if you need help in finding an attorney.
Disclaimer: I am a lawyer licensed in the State of Illinois only, and I am not your lawyer (unless you have been in my office and signed a contract). This communication is not intended as legal advice, and no attorney client relationship results. Please consult your own attorney for legal advice. This is for informational purposes only.
It is not possible to determine whether the statements were defamatory based on the information you provided. A defamatory statement is a statement of fact that has a tendency to damage your reputation in the community. As to the statement that you quit without notice, that is questionable because, on the surface, that does not impute anything wrong, immoral, or criminal to you. In fact, the law permits you to quit without notice, so it could be read innocently.
As to the other statements, it is a close question. If the individual used the phrase "might have," that is not necessarily an assertion of fact and thus may not be defamatory. I would need much more in the way of details in order to give you any legal advice. I would, however, be happy to provide you with a free consultation to discuss the matter in more detail. Please understand, however, that this answer is simply general information, it is not legal advice, I am not your lawyer, and we have no attorney-client relationship until we meet personally and you retain me pursuant to a written retainer agreement.
Also be aware that the statute of limitations for defamation claims is very short, so if you intend to take legal action, you should do so as soon as possible.
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