
Quoting
flyingron
The NY statute that covers this sort if thing is the PL 170.20 (and following sections) on possession of forged documents. This requires them to show intent to deceive someone with the document. Merely finding a fake id in your possession isn't sufficient. They'd need to see you try to buy liquor or gain entry to a bar or otherwise use the forged document.
If the lost and found or the cops or anybody else finds your wallet, it makes any difference if you told them you lost it or not.