I've read the OP and first page of responses. My first thought is that the way to work out consequences - "realistic" or otherwise - is via the action resolution mechanics. My second thought is that, if the PCs are in the stocks waiting to be executed for assaulting an evil ruler, that there might be rebels who will rescue them.
And - closely related to the idea of consequences - if the players do something that differs from what the GM would do, or from what the GM thinks is a good or sensible idea, what consequences should flow for their PCs?
More likely the rebels use the distraction of the PCs' public trial and-or execution to launch a plot somewhere else e.g. while the King and most of his guards are at the town square the rebels bust into the now-lightly-guarded palace and cause some mayhem...Umm, stocks are guarded. I suppose rebels might storm the guards to rescue two unknowns who apparently attacked the king so poorly they are merely in the stocks. It's probably more likely they would be tormented/injured by loyalists and/or children.
More likely the rebels use the distraction of the PCs' public trial and-or execution to launch a plot somewhere else e.g. while the King and most of his guards are at the town square the rebels bust into the now-lightly-guarded palace and cause some mayhem...
But D&D has never been free kriegspiel in the strictest sense. Combat is resolved via dice rolls, which means that unexpected and "illogical" things can happen.I'm of the mind that consequences in game should logically follow whatever action the PCs took.
Although I think there's something to be said, in RPGIng, for the PCs rather than NPCs being the centre of the action.I like this angle. The king is distracted, and a bigger plot unfolds, possibly allowing the players to escape due to plot convenience. As a DM I would always use an opportunity like this to move the plot in unexpected ways and surprise my players.