Will Provide Statistics for Data
The rules also say that Resistance Operatives must play a Success card. If they don't, then they are most definitely cheating.
If someone breaks a rule in a sports game are they cheating? Is a foul in basketball a cheat? Wikipedia defines cheating as: "Cheating is the getting of a reward for ability by dishonest means or finding an easy way out of an unpleasant situation". If an operative fails to play a success card are they always being dishonest? It rarely leads to win, so they're dishonestly trying to lose?
Hoyle defines these situations as "Irregularites" and for common card games has defined common remedies. Cheating is an automatic loss, and most likely no further invites to future games, with a fair bit of social shame on top--i.e. a misplay != cheating. The canonical rule book for the Resistance says an operative must play a success, however it defines no remedy.
This thread has 3 proposed rememdies:
* Play it out. (aka That'll teach 'em)
* Declare it a loss for the Resistance and start a new game.
* Declare it a void round and start a new game.
Take your pick, but declaring someone a cheat is a bit harsh.