which a marriage is void. To preserve the validity of past marriages, this part is divided into periods based on when amendments to the Act were introduced. A purported marriage is void if: either party is already married (bigamy, polygamy). the parties are in a prohibited relationship: direct descendants or siblings, including by legal adoption. the marriage was not solemnised by an authorised celebrant (as in Part IV, Division 2). there is no consent, for example due to duress, fraud, mistake as to identity, mistake as to the nature of ceremony, mental incapacity, or being below the marriageable age set out in Part II. Solemnisation of marriages Part IV, entitled "Solemnisation of Marriages in Australia", deals with who is authorised to be a wedding celebrant, and the procedures to be followed. It also contains a division on marriages by foreign diplomatic or consular officers. Authorised celebrants Division 1 deals with authorised celebrants. Under the current Act three types of celebrants are allowed: ministers of religion, state and territory officers, and civil marriage celebrants. Religious ministers Under Subdivision A, a register is kept of ministers of religion (s.27) of "recognised" denominations (s26). The only requirements for registration is that the person is a minister of religion who is nominated by their denomination, is resident in Australia, and is at least 21 years old (s29). A minister will be registered (s30) unless the registrar refuses registration because there are sufficient ministers of that denomination, or if the minister is "not a fit and proper person" or will not devote sufficient time to the functions of a minister of religion (s31). Ministers of religion are not bound to solemnise any marriage. Nothing in Part IV of the Marriage Act imposes an obligation on an authorised celebrant, being a minister of religion, to solemnise any marriage (s47). Registry office marriages Subdivision B (s.39) preserves the power of "state and territory officers", allowing people who register marriages (under a state law) to also solemnise marriages (i.e. registry marriages). Civil celebrants Subdivision C deals with "marriage celebrants", or the authorisation of people to conduct civil ceremonies. Section 39B allows the register to be kept and sections 39D-E are procedural and seek to set up processes to control the number of celebrants. This section was introduced by the Marriage Amendment Act 2002, after an attorney-general inquiry into the Civil Celebrants Program. Prior to the passage of this