Fall back (mercy) rule
The fall back (mercy) rule is where, when a team is leading by 20 points or more (10 points or more in U10's), the leading team is required to fall back behind their three (3) point line following a successful shot attempt, or whenever the opposition team in-bounds the ball. No defence may be played until the ball is dribbled or passed across the centre line. The penalty for non-compliance is a violation called by the referee with possession going to the opposing team.
The mercy rule:
9.1 Games shall consist of two halves of twenty (20) minutes. The game shall stop for timeouts in the last two (2) minutes of the second half only. The clock shall stop for all whistles in the last two (2) minutes of the second half, except where the mercy rule is in force as per bylaw 6.13 and 6.14 the clock will only stop for timeouts. No timeouts will be taken in the last one (1) minute of the first half. Where a timeout is in progress prior to the one minute point of the first half, that timeout out will cease at the one (1) minute point and the players will be called to resume play immediately.