The Responsibility Rule

'Responsibility', also known as 'pao' (パオ) is a penalty applied to a player who takes unnecessary risks around incredibly valuable hands. In general, the basic reasoning behind 'responsibility' is "If I know a player is close to a limit hand and I still give him the tiles he needs to advance his hand, the limit hand on the table is entirely my fault."

In our Japanese Riichi rules, 'responsibility' applies to the following limit hands:

• Big Four Winds (for the fourth wind pung)
• Big Three Dragons (for the third dragon pung)
• All Honors (for the fourth honor pung)
• All Terminals (for the fourth terminal pung)
• Perfect Green (for the fourth 'green' meld)
• Four Kans/Gongs (for the fourth gong)

In our Hong Kong Old Style rules, 'responsibility' also applies to Full Flush and Ruby Dragon hands.

'Responsibility' occurs when a player is only missing one meld (and possibly the pair) to complete her high value hand, and all of their other melds are open and visible. For example:

• Player A has an open pung of the green dragon and the red dragon, so it's expected that the players should be wary about discarding the white dragon, to prevent a limit hand.
• If Player B later discards a white dragon, and Player A does call it for a pung/gong, Player B becomes liable for the responsibility penalty.
• If Player A self-picks her winning tile while Player B is liable for the responsibility penalty, player B must pay the entire 384 (HKOS) or 32000 (Riichi) points for the hand (it is still scored as a self-picked win, but Player B must also pay the shares for Players C and D).
• If instead, Player A wins off of Player C's discard, both Players B and C pay 128 (HKOS) or 16000 (Riichi) points to Player A (it is scored as a win by discard off of Player C, but Player B has to split the cost).
• If, despite 'responsibility', Player B, C, or D win the hand, the lucky Player B does not suffer any further penalty.

There are a few other details about the responsibility rule.

• Even if the Perfect Green hand has four open 'green' melds, it is possible that the pair is not 'green' and that the hand would not be a limit hand.
• If Player A declares a win with a hand like this, the responsibility penalty is ignored.
• But if Player A changes her pair to be 'green' tiles before declaring a win, the responsibility penalty applies.
• The All Honors and All Terminals hands are treated the same way, as are the Full Flush and Ruby Dragon hands in our HKOS rules.
• The Four Gongs hand only qualifies for the responsibility penalty if both of the following conditions are met.
• Player A has three melds of gongs already visible at the time of the open gong taken from Player B. None of her gongs can be undeclared in her hand at the time, and an open pung that Player A turns into a promoted gong some time after taking the open gong from Player B does not qualify (The responsibility penalty is never applied retroactively).
• Player A calls an open gong off of Player B. If Player A instead calls an open pung and later upgrades it to a promoted gong, Player B is not liable for the responsibility penalty.

There is one final rule that is considered part of the responsibility penalty, but occurs under very different circumstances. If Player A discards a tile that Player B uses for an open gong, and then Player B immediately wins off of his replacement tile, it is treated as a win by discard off of Player A (but the yaku for Self-Pick still applies).

In Japanese Riichi style, a concealed gong is treated as an open meld for the purposes of responsibility. For example, if player A has a concealed gong of green dragons and a concealed gong of red dragons, and then later uses player B's discarded white dragon to complete a pung, player B is still 'responsible' for this hand. This does not occur in Hong Kong Old Style, since the tiles used in player A's concealed gongs are not visible in this ruleset.