In 2006 Western Australia passed legislation that introduced a system to check criminal records and issue permits to those who wish to work with children. In 2007, the legislation was described by the minister responsible as a "powerful system that would prevent harm to children". This paper explores that system and identifies limits to its effectiveness. The paper concluded that unless the system's limits are fully appreciated there is a possibility of a paradoxical outcome, whereby children's lives will be less safe. It also raises the question of whether in the area of record checking a national approach is not preferable to each state and territory developing its own system.