Adultery and Divorce

Is filing for divorce based on adultery the best option for you? In this guide you will find the key information relating to adultery and divorce, including what adultery is in the eyes of the law, the pros and cons, proving adultery, its effect on the divorce outcome, and the reasons why you may or may not want to choose adultery as the reason for divorce.

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Can I file a petition for divorce based on adultery?

If you have been married in the UK for at least a year, you are eligible to apply for a divorce. To do so, you must prove to the court that your marriage has irretrievably broken down. This involves choosing one of five reasons, or ‘facts’, relating to why the marriage has broken down: adultery, unreasonable behaviour, desertion (for a minimum of two years), two years separation (with consent), or five years separation (no consent required).

After ‘unreasonable behaviour’, adultery is one of the most common reasons that couples get divorced in England and Wales. You can use adultery as a reason for divorce if you can demonstrate that your partner has had consensual sexual intercourse with a member of the opposite sex, and that you find it intolerable to continue to live with them.

The person who initiates a divorce process is known as the ‘petitioner’, while the other party is known as the ‘respondent’. The choice of adultery as a ground for divorce is only available to the petitioner, or the so-called ‘innocent’ party. The person who has committed adultery can only file for divorce on those grounds if their spouse has also committed adultery.

Adultery does not have to be the only reason that you find it ‘intolerable’ to live with your spouse for you to use it as a grounds for divorce. It can be the final stage in a history of unpleasant behaviour, or one of a number of factors that have led to the living situation becoming intolerable.

It doesn’t make a difference whether you are separated or still living with your spouse: you can still file for divorce based on adultery.

What counts (or doesn’t count) as adultery in the eyes of the law?

It is important to note that what you consider to be adultery may not be the same as the legal definition, which is a specific one: adultery is legally defined as consensual intercourse with a member of the opposite sex.

This means that sexual acts other than intercourse are not considered adultery in the eyes of the law. The same goes for extra-marital relationships between members of the same sex: the infidelity must involve sexual intercourse between a man and a woman, despite the fact that same-sex marriage is legal in the UK. Same-sex relationships outside of a marriage would instead be considered ‘improper associations’ rather than adultery, and could be cited as a reason for divorce under the category of unreasonable behaviour.

Adultery has only taken place if the infidelity happens after a couple is married. A person who has been unfaithful before the marriage has not committed adultery.

It is still adultery if the couple has agreed to see other people, if the petitioner has committed adultery in the past, or if the respondent has moved in with a new partner – all while they are still married

How long can I have known about adultery for it to be grounds for a divorce?

After finding out about the adultery, you have six months to cite that adulterous act as the ground for  divorce. Once the six months has elapsed, you will have ‘condoned’ the adultery in the eyes of the court, and it can no longer be used as a reason for legal separation.

You will also be unable to file based on adultery if you remain living with your spouse beyond the six-month period. Obviously any new adulterous act then restarts the six month period.

Proving adultery in the court of law

Filing on the grounds of adultery is much more straightforward if the respondent admits to it. They will simply sign an Acknowledgement of Service to that effect, which is usually enough for the court to approve the divorce.

If the respondent does not admit that they have committed adultery, the case can turn into an expensive and lengthy legal process. The petitioner would have to prove, on the balance of probabilities, that their spouse has had consensual sexual intercourse with a person of the opposite sex. Factors that may help prove adultery in such cases might include someone becoming pregnant outside the marriage, or if the respondent is living with a new partner. However, adultery is by nature difficult to prove without a confession: circumstantial evidence is difficult to gather, and catching someone ‘in the act’ is rare. Without a confession, the person applying for divorce may instead opt to file based on unreasonable behaviour.

As there is a court fee of £592 to file for divorce, most people would want to be sure that their spouse will admit to adultery before proceeding to file for divorce on that basis. If their spouse does deny it, switching to a petition based on unreasonable behaviour could add to solicitor fees.

Does adultery affect a settlement?

Contrary to what many might think, the court will not penalise someone for having an affair, no matter how much ill-will it may have caused between the parties. There is no financial punishment for the act of adultery, nor will it affect decisions around who should have custody of the children.

Though the ‘injured’ party may believe that they are entitled to greater compensation, assets are divided regardless of who was ‘to blame’ for the breakdown of the marriage.

One advantage of this for the petitioner is that due to the lack of financial repercussions, the respondent may be less likely to contest the decision and more willing to admit to the adultery. This would guarantee quicker and more straightforward divorce proceedings.

Will the financial settlement be affected by the unfaithful spouse and their new partner living together?

While the fact of adultery alone will not affect the settlement agreement, if the person who has been unfaithful is living with a new partner and the two are ‘pooling’ their resources, this may affect the respondent’s outgoing expenditure, and thus play a role in the settlement.

Should the third party be named in the divorce?

Naming the third party or ‘co-respondent’ involved in the adultery is an option when filing for divorce on these grounds. However, it is absolutely not necessary to name them, and doing so can lead to further complications.

This is because the third party would be invited to join the proceedings, which may prolong the length, expense, and potential for conflict in the case. Therefore, even though some people may feel compelled to name the co-respondent out of anger or upset, it is in most cases unfavourable for them to do so.

Why choose adultery as grounds for divorce? A summary of the pros and cons

Adultery might appeal to a petitioner on the grounds that it can be more straightforward and less acrimonious than filing based on unreasonable behaviour – assuming their spouse admits to it. Applying based on unreasonable behaviour may involve listing multiple examples of the respondent’s conduct that the petitioner finds intolerable, leading to greater tension or resentment between the parties. Filing on these grounds could also be a lengthier process in court than the grounds of adultery, if the adultery is clear and undisputed

The fact that the unfaithful partner will not receive a lesser financial settlement by admitting to adultery may also make things easier, as it removes incentives for them to contest the divorce.

Moreover, filing based on adultery may actually present unexpected opportunities for resolving financial issues. The respondent may feel guilty about what they have done, or wish to move on and remarry as quickly as possible. Either of these reasons might lead them to agree to a less favourable settlement than they otherwise would have.

Problems with choosing adultery as grounds for divorce arise if the respondent does not admit to it. The legal fees of having to prove the adultery on a balance of probabilities – as well as the court fees – mean that it can be a potentially expensive and fraught way to divorce.

Another drawback to taking the adultery route is its narrow definition. There are many forms of infidelity that are not covered under the legal definition of adultery, and this narrowness is inadequate for many. Unreasonable behaviour provides for a broader scope, including the suspicion that a partner may have been unfaithful. Therefore, if someone wishes to file for divorce and they are not sure that their spouse will admit to adultery, the fact of unreasonable behaviour would be a more appropriate choice. Unreasonable behaviour also covers any other conduct on the part of the respondent that the partner desiring a divorce cannot reasonably be expected to live with.

Finally, in the eyes of the law you are no more likely to get a better financial settlement if you choose adultery as grounds for divorce, even if you are the ‘innocent’ party and your partner admits to having an affair under the legal definition of adultery. The reasons a marriage has ended – and who should be ‘blamed’ for its breakdown – are not relevant to the court when it considers how assets should be divided.

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