What should the marker do if they accidentally move the jack with the measuring tape?

The marker is responsible for ensuring that the game runs smoothly and fairly. If the jack is accidentally moved while using the measuring tape, the appropriate action is to return the jack to a position that is agreed upon by both opponents. This maintains the integrity of the game, as both players have a vested interest in ensuring that the jack is placed correctly. By requiring consensus between the opponents, it fosters fairness and collaboration, which are key principles in the sport of bowls.

Returning the jack to a mutually agreed-upon location is preferable because it encourages transparency and agreement among players, reducing the chance of disputes later in the game. This practice is consistent with the principles of sportsmanship and respect in competitive play.