Okay, lets start over. :)
1) All U.S. banks are subject to federal code stating that a check can be declined after 180 days, or approximately six months, after it was written. California does not have any laws that extend or reduce this period. The issuing bank still has the option to cash or decline a personal check after 180 days have passed. Some banks will still honor a check in this case and some will not. Clearly, your bank would not cash the checks if plaintiff tried to recently present them. Now, as long as the plaintiff is within the statute of limitations based on the ORIGNIAL injury she is claiming, then she can sue. We have to dig a little deeper to see if she is still within that time frame. So, let's say you had an oral contract with the plaintiff to pay her weekly for this money pot. The plaintiff apparently believes that when she tried to collect the money from you, you paid her in the form of two checks. She does not remember you gave her cash. Several years go by and she finds the checks. Forgetting that you already paid her the money in cash, she sues to collect on the checks because the bank will not cash them for her now. However, because you wrote these checks back in 2009, the plaintiff should be BARRED by the statute of limitations on oral contracts, which happens to be 2 years in the state of CA. Thus, you need to ask the judge to dismiss the lawsuit based on the fact that the statute of limitations on your oral promise to pay is up. That will be your first argument.
2) No, what she is doing was not even legal. If a contract is illegal then it is void as a matter of law. Thus, the duties arising from it are void as well. You should not have to pay the plaintiff for something that was illegal in the first place. This will be your second argument.
3) As we already discussed previously, and if the judge does not dismiss the case based on the above two reasons, you are going to have to take your bank records into the hearing with you and argue that you already paid this woman. You don't have any other proof besides your bank records showing withdrawals at this time, so you cannot offer anything more than that. Honestly, the case should not even get this far because it should be dismissed on #1 and #2 above, but if for some slight chance it isn't and the judge really wants to hear if there is a case and controversy, then you will show him the evidence you have, tell him your side of things, and hopefully this will be enough to convince him to enter a judgment in your favor. Many times, these small claims cases come down to credibility, that is, who the judge believes more. So keep that in mind when you are speaking.
Hope this helps to clarify. If you still have questions, please just let me know. If not, please consider a positive rating at this time. Thanks Kim!