Further , membership in the order only grants precedence within the society , which is as follows : Precedence within each grade is dictated by date of appointment , save for those in Grade I who are either a head of state or royal , in which case they all precede the other members of the grade in the following order : Following constitutional changes made in 1999 , the Priory of England and The Islands was established ( including the Commandery of Ards in Northern Ireland ) alongside the existing Priories of Wales , Scotland , Canada , Australia ( including the Commandery of Western Australia ) , New Zealand , South Africa , and the United States .
Further , membership in the order only grants precedence within the society , which is as follows : Precedence within each grade is dictated by dates of appointment , save for those in Grade I who are either a head of state or a member of the royal family of a Commonwealth realm , another Commonwealth country , or foreign state , in which case they all precede the other members of the grade in the following order : Following constitutional changes made in 1999 , the Priory of England and The Islands was established ( including the Commandery of Ards in Northern Ireland ) alongside the existing Priories of Wales , Scotland , Canada , Australia ( including the Commandery of Western Australia ) , New Zealand , South Africa , and , since 1996 , the United States , each of which is governed by a Prior and a Priory Chapter .