If you’ve seen the James Bond classic Octopussy, you might be familiar with the term “player’s privilege” in backgammon.
On the last roll, Bond needs a 6-6 to win, so he calls out “player’s privilege,” allowing one player to exchange his dice for his opponent’s. The loaded dice are still in Khan’s cup, but he can’t complain without revealing himself. So Bond takes the cup, rolls 6-6, and wins.
Despite being in a memorable 007 movie, player’s privilege is a purely fictitious rule. In money games, you’ll need to be as suave as Bond to think you can get away with such a move. Dice can be switched, but only between games. But when playing amongst friends, we don’t see it being a problem.