How do I report people I see using handicapped spaces without the placard or plate?

It's one of my biggest pet-peeves, and I know a lot of you say no one would ever do it, but I see it all the time, usually lazy teens from the local college. And even if they had some invisible disability that doesn't seem to affect walking to and fro, the law is very clear that you have to have the placard or plate or both.

There is a fine, but cops tend to be too lazy to enforce it. Someone mentioned before there's a way to report it with a photo, but I'm not sure who to send it to. And as a gig worker I can tell you people in the forums proudly admit they take those spots because they don't care and aren't walking. So people are abusing those spots.