I think what you may have observed previously is that a "reasonable facsimile of the wheelchair symbol" may be used, in some state jurisdictions. When I google, "reasonable facsimile wheelchair symbol", I find that Michigan, Indiana, Georgia, and Connecticut provide this language in connection to the use of the international wheelchair symbol in providing pubic notice of the availability of various ADA accommodations.
Unfortunately, I find nothing like this language for California.
Assuming that the language you recall doesn't exist, then your case in traffic court can't rely on the language, except as it relates to your intent to defraud for purposes of that felony that the law enforcement officer was discussing.
Vehicle Code 4463(a) makes it a felony where a person "Alters, forges, counterfeits, or falsifies a certificate of ownership, registration card, certificate, license, license plate, device issued pursuant to Section 4853, special plate, or permit provided for by this code...." -- but, only if the person has the "intent to prejudice, damage, or defraud." So, you have a defense to this allegation. Also, I don't believe you were actually cited for a felony, because if you were, the officer would have arrested you on the spot. I think the officer was trying to scare you, and only cited you for the traffic offense: VC 22507.8(a).
That said, you apparently violated the law by displaying your "reasonable facsimile." Section 22507.8(a) provides: " It is unlawful for any person to park or leave standing any vehicle in a stall or space designated for disabled persons and disabled veterans pursuant to Section 22511.7 or 22511.8 of this code or Section 14679 of the Government Code, unless the vehicle displays either a special identification license plate issued pursuant to Section 5007 or a distinguishing placard issued pursuant to Section 22511.55 or 22511.59."
My experience with these types of issues is that if you explain what you were doing, and acknowledge that you made a really dumb error -- but, that you have a current, valid handicapped placard, and that had you realized you were not entitled to display a reasonable facsimile, you would have displayed the valid placard and not the fake.
I'm betting that the judge will dismiss the case in the interests of justice, because the entire point of these laws is to protect handicapped persons -- not to punish them.
I hope I've answered your question. Please let me know if you require further clarification. And, please provide a positive feedback rating for my answer -- otherwise, I receive nothing for my efforts in your behalf.
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