If you’re referring to the wavy pattern along the cutting edge, that’s not from the folding process. The hamon is added to the blade during the quenching process, by adding clay to the steel. The clay causes the covered steel to heat differently than the uncovered steel. That differential heating is what is visible as the hamon.
It’s largely decorative, but does have function as it determines what part of the blade can be sharpened to an edge.
Nah, they don’t get the benefit of the doubt anymore. “I smelled weed” has been used for decades to skirt probable cause requirements. Because it’s transient evidence that can’t be saved or replicated, and you can’t prove that they’re lying. You can be 100% clean, but a cop claims he smelled weed and now your car’s interior paneling is getting ripped out on the side of the highway.
The cop lied to get the search approved. No more, no less.