In Australia, infidelity is one of the top four most common reasons for divorce. Unfortunately, when a marriage ends due to adultery, the resulting legal battle is frequently combative and emotionally turbulent.

If you were the one cheated on, you're likely wondering if your spouse's behaviour will benefit you legally, financially, or in some other way. Likewise, if you were the unfaithful spouse, you might be concerned that you're at a disadvantage in the eyes of the law.

Here's a closer look at what happens in a divorce if you have committed adultery, including how it might affect property settlements and financial decisions. 

What Is Infidelity?

So what are we talking about when we say “infidelity”?

While all couples have different agreements about what is and isn't allowed in a relationship, the most widely-used definition of infidelity refers to someone having a physical affair with a person who isn't their spouse.

Aside from physical intimacy, many couples also consider emotional and online affairs other types of infidelity.

But as you’ll see, the definition doesn’t actually change things too much.

History of Family Court System

Before we leap in, it’s probably a good idea to understand how we got to where we are.

Today's divorce laws are relatively new (in legal terms, at least). Until 1975, the only way to get a divorce in Australia was to prove that the marriage had failed due to your spouse's actions.

Along with adultery, other grounds for divorce included drunkenness, abuse, lack of affection, mental illness, and more.

This is because the law considered marriage a contract, and treated it accordingly. To void the contract, one of the parties had to violate the terms, meaning issues related to the vows, such as fidelity, faithfulness, support, etc.

As a result, divorce cases often involved private investigators, false claims, and other underhanded techniques to "win" – as the "wronged" party could receive a larger property settlement.

Ultimately, the Family Law Act updated and refreshed the legal framework, establishing no-fault divorce.

How Does Infidelity Affect a Divorce?

For better or worse, a spouse's infidelity rarely impacts legal issues related to divorce or the process leading up to it.

Australia uses a "no-fault" divorce system.

This means neither party is considered legally responsible in a divorce. Instead, the only legal reason needed for divorce is what the law describes as an "irretrievable breakdown of marriage," as evidenced by a separation period of no less than 12 months.

It's a broad description that essentially means either party can file for divorce without specifying a reason.

Part of the reason for this is that in Australia divorce is a different thing from the separation process.

So, the Act separates the technical divorce from:

• Property settlement;
• Spousal maintenance;
• Child maintenance; and
• Child custody

Each aspect is assessed on its own merits. 

Property Settlements

Property settlement is the process of distributing assets formerly shared by the two parties.

The courts divide property equitably, which doesn't necessarily mean equally.

Instead, the court is going to look at all the circumstances, including:

• The income of each individual
• Homemaking and other non-financial duties
• Child care
• Each party's age, health, and earning capacity

Realistically though, infidelity doesn’t really come into play. In practical terms, a cheating spouse doesn't have to pay more because they were unfaithful. 

One exception here might be in the event of a binding financial agreement (pre-nup) which could affect outcomes on property settlements.

Spousal Maintenance

The Family Act also established rules regarding spousal or defacto maintenance. If either spouse (or de facto partner) cannot support themselves, the other party must generally provide financial assistance.

The amount one spouse provides is, again, determined looking at all the circumstances including:

• Age
• Health
• Current incomes, savings, and other financial resources
• A suitable and fair standard of living

As with property settlements, infidelity isn't a factor considered by the courts. An unfaithful partner won’t be “punished” by having higher spousal maintenance contributions to make. Nor with the non-cheating spouse get out of financial maintenance purely because their ex cheated on them.

Child Maintenance

Child custody and entitlements are also unaffected by infidelity.

Instead, the Family Act directs the court to consider two issues:

• Maintaining a meaningful relationship with both parents as much as possible
• Protecting the children from any type of violence, neglect, or abuse (physical or psychological)

Ultimately it is the interests of the child that are considered paramount.

In theory, therefore, infidelity could be a factor if one spouse moves in with a new partner should this be found to have a material impact on the wellbeing of the child.

The Circumstances Where Infidelity Influences Divorce Law

Although rare, a few situations exist where adultery in divorce allows the court to alter property division.

First, there's the issue of wastage. This is where the cheating partner spent copious amounts of money during their infidelity, such as taking their boyfriend or girlfriend on lavish trips or buying expensive gifts.

While each situation is different, buying a dinner or two probably won't make much of a difference, legally speaking. A wastage argument requires solid evidence that the spending resulted in a negligent or reckless decrease in the matrimonial property pool - family savings, property, and so on (discussed here).

Note that infidelity isn't the only reason a spouse can be found financially negligent. Other examples include:

• Excessive gambling
• Wasteful spending
• Risky investments

Final Thoughts

What happens in a divorce if you have committed adultery?

Generally speaking: not much.

While divorce due to infidelity is certainly an emotional and upsetting time for most people, ultimately in most circumstances the legal outcomes are going to be fairly similar.