It sounds like NY state's laws on knives are broad and vague. While the law pays specific attention to a few particular kinds of knives (like switchblades) a 3-inch blade that doesn't meet any specific criteria can be judged an illegal "dangerous knife" if the owner says it's necessary for protection, even if it was never used or even brandished as a weapon. https://www.akti.org/state-knife-laws/new-york/
We're in this weird world where you can carry a gun around and it's considered your right to do so, and but carrying a pocketknife or a leatherman might be a crime. You can wear a t-shirt with a hate-speech slogan, and you can wear kkk robes, but the minute you put on the hood that obscures your face, or god forbid a ski-mask, that's when you've apparently crossed a line. How did we get here?