Rolling the Dice, Break the Wall (Article ID 148)
Abstract: In all games there are rules in place to ensure fair play, and this applies to American Mah Jongg. Rolling the dice to break the wall is similar to cutting a dead of cards and prevents cheating.
Question from Player: My group doesn’t roll the dice and break the wall. We had a sub who insisted it is a mah jongg league rule. Is it a rule and if so, what is the reason?
Answer from NMJL: “Rolling the dice is a NMJL rule. Think of this rule akin to “cutting” a deck of cards before you play. It makes cheating virtually impossible.”
Source: National Mah Jongg League Bulletin (2021)