While an employer's submission of falsified documents is illegal, that does not negate the fact that you resigned from your most recent position. Generally speaking, individuals who resign are disqualified from collecting benefits. This is because UI benefits are available only to those employees who are unemployed "through no fault of their own." The EDD reasons that individuals who quit are unemployed "through fault" since they made the voluntary decision to become unemployed.
Certain limited exceptions to this general principle arise where the claimant quits with "good cause." I suggest that you review the EDD's summary of those exceptions here: http://www.edd.ca.gov/uibdg/Voluntary_Quit_-_Table_of_Contents.htm
Unless an exception applies, a claim for benefits will ordinarily be denied if you quit, regardless of whether your employer falsified documents pertaining to your claim.
This answer is a general interpretation of the law and is not fact specific to your case. Likewise it does not create an attorney-client relationship. You should seek an attorney for a review of your specific facts and documents.
All you can do is testify at the hearing about the falsity of the papers. But the real issue is whether you had good cause to quit.
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I agree with Mr. Mallen. Your only real "defense" to the false statements is for you to counter those statements with evidence of your own. If you have any documents that support you, submit them. Otherwise, state the truthful facts and hope you are believed.
Good luck to you.
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