Generally speaking, absent a contractual right that would require cause for termination, an employer can fire you for any reason or no reason at all, so long as the reason isn't prohibited by law (such as discrimination based on race, religion, sex, age, disability). If the reason for the termination was a yelp review, it might not be "fair", but it wouldn't be grounds for a lawsuit. If, on the other hand, the reason you were singled out for termination was some sort of protected reason (for instance, your race, religion, sex, age or disability), that MIGHT be grounds for a claim. You would need to discuss further with an employment lawyer in CA to determine if any of those protections might apply.
Answers to questions are meant to be general only, are not intended to be legal advice and do not create an attorney-client relationship. Answers to questions are based on NY law, and the laws of other states may create different rights and obligations.
You don't say what kind of work you do or the nature of the review, but I will assume you are an "at-will" employee and that the review included some form of a critique which reflected poorly on you. Unless you have a contract which restricts the ability of an employer to terminate the employment relationship, an employer may terminate for any reason not prohibited by law. This would include things such as customer complaints, whether founded or not. Wrongful termination does not include being terminated unfairly.
If you have reason to believe the real reason for why you were terminated was an unlawful reason, such as age, race, gender, handicap (to name a few protected classifications), or in retaliation for engaging in a protected activity, you should consult with an experienced employment law attorney.
They say you get what you pay for, and this response is free, so take it for what it is worth. This is my opinion based on very limited information. My opinion should not be taken as legal advice. For true advice, we would require a confidential consultation where I would ask you questions and get your complete story. This is a public forum, so remember, nothing here is confidential. Nor am I your attorney. I do not know who you are and you have not hired me to provide any legal service. To do so would require us to meet and sign written retainer agreement. My responses are intended for general information only.
Although I substantially agree with the other two answers posted by my colleagues to your question, I take issue with the proposition that you ought to consult with an employment lawyer. There is nothing in the facts you describe that causes me to suspect that you were terminated for a reason the law prohibits. Assuming you were an at-will employee terminated because of the content of a consumer's Yelp review, I know of no general principle of law that prohibits your discharge. What you describe sounds unfair to me, but not unlawful. And I strongly suspect that if you were to consult in person with an employment lawyer, s/he would tell you the same thing.
All of which is to say, I don't agree that you ought to go get a consult with an employment lawyer. That's just something lawyers say to give themselves cover in case they missed something important. Such advice results in employment lawyers' getting even more phone calls from legitimately terminated employees who haven't suffered harms for which the law provides a remedy, but who expect the lawyer to counsel them for free. I see no claim here.
Good luck with your job search.
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