I should note that the recommendation regarding 'mandated reporters' would not include Jehovah's Witnesses as they are neither a regulated activity in relation to children, nor in a position of trust (as defined by the Sexual Offences Act 2003
Elders are in a position of trust. Surely you are not suggesting they aren't? I thought that had been established in the majority of western cases. Watchtower's elders 'are clergy/are not clergy' manoeuvres have been found out and debunked!
In the UK we don't have mandatory reporting in all cases for the reasons Earnest noted in bold type above. Victims and families/child services have fears around teenage relationships where, for example, a teenaged girl and her boyfriend of similar age may be reluctant to access contraception for fear of being reported.