Parliamentary ping-pong

Parliamentary ping-pong is a phrase used to describe a phenomenon in the Parliament of the United Kingdom, in which a bill appears to rapidly bounce back and forth between the two chambers like a ping-pong ball bounces between the players in a game of table tennis.

"Lutte a la corde" (French, meaning tug of war, lit. "struggle of the rope") is an older term for Parliamentary ping-pong. Believed to derive from the Norman French, in recent times it has fallen out of common usage.

The British Parliament is bicameral, consisting of the House of Commons and the House of Lords. The rule is that before a Bill can receive the Royal Assent and become law, it must be passed in its final form by both the Commons and the Lords without changes. If one of the Houses makes any change or amendment to it, the other House has to agree to those changes, or make counter-changes of its own, in which case it returns to the other House.

The debates in which the Bill is considered are usually scheduled weeks or months apart. However, in some circumstances the normal legislative procedure is radically accelerated to the extent that the proposed law, or Bill, appears to bounce back and forth between the two chambers like a ping-pong ball.

However, in certain circumstances when there is a non-negotiable time limit, and the two Houses disagree vehemently on the matter, this process can be speeded up to less than six hours per cycle, and carries on until one of the sides caves in.

Usually the time limit is imposed by the end of the Parliamentary session when all business, including incomplete Bills, simply gets erased from the books and has to start again. This usually occurs at the State Opening of Parliament some time in November; Parliament can continue working on the previous year right up to the night before. Another instance is the wash-up period of a few days between the calling of a general election and the ensuing dissolution.

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