33. INTERFERENCE WITH THE POSITION OF A BALL

1. INTERFERENCE BY THE STRIKER If the striker interferes with a ball during the striking period, Law 28 applies if the interference is discovered before the limit of claims of the error. In all other cases, Law 33(d) applies and the striker continues his turn subject to the law applicable to any other error or interference that may have occurred.
2. INTERFERENCE BY THE ADVERSARY OR AN OUTSIDE AGENCY If the outcome of a stroke is materially affected because the adversary or an outside agency has interfered with the position or motion of a ball and the interference is discovered before the next stroke, the stroke is replayed after replacing the balls in their lawful positions before the stroke was played. In all other cases, Law 33(d) applies.
3. OTHER INTERFERENCE In all other cases, including the effect of extreme weather conditions, if a ball at rest moves or is moved between strokes or during a stroke that did not affect its position, it is deemed to have suffered interference, there is no penalty and Law 33(d) applies.
4. REPLACEMENT OF A BALL AFTER INTERFERENCE If the ball was a ball at rest, it is replaced. If it was moving, it is placed where it would otherwise have come to rest. After interference during a stroke, a ball cannot subsequently in that stroke make a roquet, be roqueted, score a point for itself or cause another ball to move or score a point.