It is illegal to fire someone for having engaged in whistleblowing at a previous job. See Ca. Lab. Code §1102.5(d). It actually wouldn't have mattered whether the employer found out from you or from someone else, except that it is easier to prove their motivation since they found out from you directly.
As in all of these cases, the issue is primarily one of proof. The timing in your case is clearly suspicious, and it is certainly good news for you that you had a positive performance review 3 months prior.
If you believe that you have been retaliated against for your prior whistleblowing activity, it is important that you take action within your statute of limitations or your right to do so may be lost forever.
I hope this information is helpful to you.
Craig T. Byrnes
Disclaimer: Please be aware that I am not offering legal advice, nor forming an attorney-client relationship with you. I am not representing you, nor doing anything to protect your legal rights. If you believe that you have suffered a legal wrong, take action before any statute or limitations expires, or your right to do so may be lost forever. Good luck in your legal matter.
This Q&A board is not a place to recruit attorneys. If that is your intent, I would suggest you look either on this site in the Find a Lawyer section, or go to www.cela.org, the home page for the California Employment Lawyers Association, an organization whose members are dedicated to the representation of employees against their employers.
Good luck to you.
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