Wendy recently saw this post: When You Hit The Ceiling In Indoor Tennis. That post discusses exactly what happens when a lob hits the ceiling on an indoor tennis court. Specifically, it explains that the ceiling is a permanent fixture and, per Rule 13 of the USTA's Official Rules of Tennis, if a ball touches a permanent fixture before it hits the proper court (the opposing player's court), the player who hit the ball loses the point.
Now, while you would think it would be obvious whether or not a ball hits the ceiling, I can imagine a ball barely grazing the ceiling and there being a dispute. Look, I play in an indoor league on Fridays that is a very “competitive” league (and that is putting it nicely). Balls are often lobbed pretty high and I can see a dispute breaking out over whether or not a ball actually hit the ceiling.
As far as who makes the call in this situation, here is what I think:
While we know the outcome when a ball hits the ceiling (see the post cited above), the rules do not address the issue of who makes that call. So you have to go to The Code which governs the conduct of players in tennis matches.
This exact situation (hitting the ceiling) is not discussed. But I believe Paragraph 5 of the Code applies here. That paragraph states –
Player makes calls on own side of net. A player calls all shots landing on, or aimed at, the player's side of the court.
So if your opponent hits the lob, and it is obviously aimed at your side of the court, you get to make the call. And if your call is that the lob hit the ceiling, you win the point.
Thanks to Wendy for this great question. I really had to think about it. And now I'll be ready with the answer if it ever comes up in one of my own indoor matches.