10 / 10 / 2023


What is bigamy?

Bigamy is the act of entering into a marriage with one person while still legally married to another. Bigamy is currently a federal offence in Australia under section 94 of the Marriage Act 1961 (Cth) which states ‘a person who is married shall not go through a form or ceremony of marriage with any person’. Offences of bigamy are very rare. The offence carries a maximum penalty of 5 years imprisonment. If the offence is heard summarily in a local court the maximum penalty is 12-months imprisonment.

History of Bigamy

The offence was first created by a statute of James I around 1603, and had its origins as a legal offence derived from societal and religious moral concerns that the actions constituting the offence were to dishonour God and would be a detriment to the children of a marriage. In Attorney-General (VICT.) v. The Commonwealth (1962) 107 CLR 529 at 576, His Honour Justice Menzies KBE states:

In support of the contrary conclusion, we were referred to the preamble of the Statute of James I of 1603 creating the crime of bigamy, which it was said showed that bigamy became a crime because it was regarded both as a sin and a vice involving “great dishonour of God and the undoing of divers honest men’s children”.

In Thomas v. The King (1937) 59 CLR 279 Evatt J mirrored the historical basis of the offence of Bigamy by noting that its purpose was to protect an existing status (of marriage). This decision also noted that the offence of Bigamy serves a purpose to unsuspecting persons who intend to assume such a status (at 316).

Since 1603 and indeed since 1937, marriage has assumed a secular status and the protection of a religious status to marriage through criminal law is of less or little modern relevance. Admittedly, however, in line with decisions such as Thomas there remains an element of moral deterrence in the offence of preventing a partner from being deceived.

Defences to Bigamy

There may be no suggestion of any aspect of a defendant’s behaviour which indicates the type of deception inherent in a man simultaneously maintaining different romantic relationships with two different women. Nor may there be any suggestion of any other form of moral misbehaviour in regard to any romantic relationship relevant to the events that become subject of these charges. However, bigamy is to be adjudicated with strict liability and as such the potential lack of immorality is not a defence available.

It is a defence to the prosecution of bigamy if the defendant proves:

  1. At the time of entering a second marriage, the defendant believed that his or her spouse was dead; and
  2. The defendant’s spouse had been absent from the defendant for such time and in such circumstances as to provide, at the time of the alleged offence, reasonable grounds for presuming that the defendant’s spouse was dead.

Proof by the defendant that their spouse had been continually absent from the defendant for the period of 7 years immediately preceding the date of the alleged offence and that, at the time of the alleged offence, the defendant had no reason to believe that their spouse had been alive at any time within that period is sufficient proof. However, the defence of mistake of fact does not apply.

According to a 1986 report by the Australian Law Reform Commission, the Prosecution would also have to prove beyond a reasonable doubt that the form or ceremony of marriage was one under the Act. Thus, the certain kinds of polygamous traditional Aboriginal marriages would not be considered a form or ceremony of marriage and therefore bigamy cannot be established. Simply put, the marriage ceremony must prima facie confer the status of husband and wife on the two persons.

Other Relevant Offences

In Australia, for a marriage to take place both parties must each sign a written notice and declaration which requires them to specify their current conjugal status and the belief that this is no legal impediment to the marriage. On this notice, there is a specific box which requires parties to tick, stating “neither of us is married to another person”.

It is an offence punishable by 8 months’ imprisonment under section 104 for a person to give a notice to an authorised celebrant, or sign a notice after it has been given, to the knowledge of that person, where the notice contains a false statement or an error or is defective. For example, if a person who has previously been married, or is currently married, declares that they have not been married or is not currently married, they may be committing the offence of giving a defective notice.

Despite being derived from a Statue created in 1603, the offence of Bigamy remains in Australian law. Key justifications put forward for the need for the offence – such as religious reasons, illegitimacy of children, deception or spousal desertion – seem to be waning.

The creation of laws in Australia have been designed to protect spouses and children not only in marriages but in de facto relationships, which are now often considered equal to marriages before the Courts. The Family Law Act, namely spousal maintenance, and Child Support schemes provide protections to all parties from deserting spouses.

Marriages have moved away from the religious institutes and are treated as secular civil matters. Same-sex marriage and divorce are legal and prominent in the Australian system.

An argument for the continuation of bigamy is that it could be considered a form of deception, that is a person deceives another into entering into a marriage whilst still being married to someone else. The deception could be grounded in an attempt to receive some greater benefit such as immigration status, welfare or consent to a sexual activity. But what happens if there is no deception – if both parties were aware and there was no overlap in relationships?

The preconceived bias against bigamy is that of immorality and its connection with adulterous ways of life. However, adultery itself is not a criminal offence and there would be no reason to think by participating in a form or ceremony of marriage somehow increases its criminality to the point of requiring an offence.

Bigamy as an offence often provides a wide range of opinions and discussions – but as a matter of fact it is still illegal in Australia for a person who is married to go through a form or ceremony of marriage with any person.

Callum Parker, Lawyer