I've done it quite often over the years, especially since cell phones came along. Most of them have been reports of drunk drivers, and I would suppose that the police were happy I called them. The oddest times I've called involved the railroad police. I'm a trainwatcher, and sometimes you see things that the railroad should know about. Problem is, in probably 20 or so times I've called, they (Conrail, CSX, and NS) have never, ever, relayed what I reported correctly, not one time. One time, a big train passed me, and on the last locomotive, there were sparks shooting out of the back truck, and a small amount of fire was coming out on top of the truck. I called Norfolk Southern and talked to someone in Philadelphia. I told them what the train was and where it was presently at. A few minutes later, it comes over the scanner. All they got right was the train symbol, nothing else, and of course, they didn't find anything, so the train kept going. About the time I called again, to try to tell them they had totally fouled up, I didn't have to call, as the loco's alarms went off, and by then, 20 minutes after I called, the problem was a lot worse, and the loco was dead. Similar things happened every time I called, so if it's not a major safety hazard, I don't call anymore. That's more for me not feeling guilty about not calling if someone gets hurt or killed, since it's not likely they will get that call right either. The last time I called, a brake was locked up and the wheel was glowing a dull red, and I called. They messed up the report, of course, but they did stop the train and find the problem, but they were looking for some other problem entirely. Some of the warped reports were pretty comical.