DISCARDED TILE BEFORE A PICK CAN NOT BE CALLED (Article 9)

Commentary: When a player discards before picking a tile from the wall, another player cannot claim the discard for an exposure.

The answer from the league does not speak to a situation where the invalid discard can give someone mah jongg, so you must decide how to handle the problem as a group. It can be inferred that a mah jongg would be honored considering this rule: If a player picks and discards out of turn. Another player calls that tile for Mah Jongg; the out-of-turn player pays for the entire table (source MJME 2020 pg 31).

Question from a player: Someone threw a tile before they picked. Before the player’s hand was declared “dead” a player called the tile that was thrown. Can they claim that tile?

Answer from the NMJL: No. You may not call a discarded tile that was thrown before a tile was picked.

Source: National Mah Jongg League Bulletin (2022)