An employer's fraudulent inducement to a potential employee to relocate is a serious matter. By statute, the employer is liable for treble damages.
The problem is proving the fraud. The statement to you was oral, and you would have to prove that they did not in fact contemplate what they said. Nonetheless, you still should consult a lawyer who can discuss the risks and rewards of litigation.
Under Labor Code 970 and 972, an employer who induces an employee to move into or out of California based upon false representations of working conditions, salary, etc. is liable for double damages. In addition, you may have a fraud in the inducement claim.
However, fraud claims based upon oral representations are more difficult to prove, because the defendant will typically dispute that the representation was made. You should look to see if that statement was confirmed in any email or other writings.
My colleagues have addressed the (depression-era) statutes about luring people to California for (non-existent) jobs and the difficulties in proving fraud. Add to this that you appear to be contemplating suing a government agency and you face even more legal/administrative hurdles. It does not seem like a strong case to me, but other attorneys may differ.
The above is general legal and business analysis. It is not "legal advice" but analysis, and different lawyers may analyse this matter differently, especially if there are additional facts not reflected in the question. I am not your attorney until retained by a written retainer agreement signed by both of us. I am only licensed in California. See also avvo.com terms and conditions item 9, incorporated as if it was reprinted here.
"I was offered the job and then declined when the pay, benefits and other compensation where made known to me." This statement is inconsistent with your final statement that you moved and took the job. If you actually took the job, I agree that you should personally seek the services of an attorney who can review the facts with you. However, IMO, your case is weak if this is your evidence. There are, in all probability, facts not stated that undercut your alleged claim. IMO, this email fails to meet the higher standard of proof required, i.e., clear and convincing evidence of fraud.
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