Regardless of being against the law or not, if his employers see it they might not be too happy about it.
Which they wont because guess what? It's not on anything that my work can easily see.
We had a very similar issue the other day on a nother forum. A guy likes to... bring home his lady friends and posts about his womanizing. Recently he has had to go back and remove some posts, as he wants to be a teacher and shit like that could ruin you. In fact doing donuts in an ambulance would probably cause a health department scandal. I know that if the media over here found out about something like that, they would hold a Royal Commission into the conduct of ambulance drivers
Nobody gives a shit about stuff like that over where I live. A cop passed me while I was doing it. He could have done something (namely a ticket and 2 points on my license for wreckless driving) but he didn't. You can't miss an ambulance doing donuts in a parking lot (with another ambulance parked with me).
Not only that, he could have also just called up my job and complained, at which point they could have done something then. But they didn't.
In fact, it's not entirely frowned upon. We're hooked up to GPS which tracks all the rigs in the fleet. Why else would I be in a parking lot that big during heavy snow time? Not only that, but the camera's at base have seen rigs fly into the lot to slide-park into their spots.
I'll be fine, thanks for the concern otherwise.