Rapid Succession Discard and Who Pays Double (Article ID 98)
Abstract: If two identical tiles are discarded, one right after the other, and someone calls the tile for mah jongg, it is the 2nd discarded tile that can be claimed. Therefore, the player who discarded the second identical tile pays double the hand’s value shown on the card.
Question from a player: I discarded a 3 Bam and the next player also discarded a 3 Bam. The 3 Bam was called for mah jongg. Who pays double value?
Answer from the NMJL: “The second discarder pays double value as the first 3 Bam was covered by the second discard.”
Source: Mah Jongg Made Easy (2020 page 26, Standard Scoring); National Mah Jongg League Bulletin Q&A (2007, 2014) https://www.nationalmahjonggleague.org