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What is unreasonable behaviour in divorce?

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Unreasonable behaviour is one of the five facts you can use to prove that your marriage has irretrievably broken down so that you can obtain a divorce. (You can read more about the other facts here).  

Of the 90,871 divorces in England Wales in 2018, the most common reason for divorce was unreasonable behaviour.  Over 50% of women and 36% of men in opposite-sex marriages, cited this as the grounds for divorce in their petition. 

In the current absence of a no-fault divorce system* in England and Wales, using unreasonable behaviour can be a quicker way to end your marriage (as opposed to waiting for the minimum period of 2-years separation). 

What is unreasonable behaviour? 

In short, almost any behaviour that the petitioner (the person issuing the divorce petition) finds to be unacceptable and cannot be reasonably expected to live with can amount to unreasonable behaviour. 

If the behaviour complained of is of a serious nature, then only one allegation may be enough. On the other hand, if the behaviour is not particularly serious then the court is likely to require more than one allegation, in order to be satisfied that the marriage has irretrievably broken down.

What are examples of unreasonable behaviour? 

There is no definitive list of unreasonable behaviours used in a divorce petition. 

Sometimes a couple has simply grown apart and struggle to find any challenging behaviours. At other times, we have worked with clients petitioning due to some unusual behaviours including spying, going vegan, lack of DIY skills (you can read more here). 

Some of the most common reasons are listed below. 

  • Abusive behaviour, physical, verbal or mental 
  • Debt / financial recklessness
  • Inappropriate relationship or suspicious of affairs (To cite adultery your spouse has to admit that they have had sex with a member of the opposite sex, or you would have to prove this)
  • Unreasonable sexual demands
  • Addiction 
  • Family disputes
  • Spending too much time at work/socialising/exercising 
  • Refuses to discuss relationship issues  

How should you detail unreasonable behaviour? 

Allegations of unreasonable behaviour must be sufficient to satisfy a judge to accept them and grant the divorce. However, it is considered good practice to include only as much as is needed to satisfy the test, rather than to include significant detail which may inflame the situation.

You will need to provide specific examples about what, when and how it made you feel. 

Mistakes made at this stage can become time-consuming, especially if the petition is rejected and needs to be resubmitted, particularly given the delays that the courts are experiencing at the present time.

Specialist legal advice from a divorce lawyer will ensure that the allegations are worded correctly for the courts and that the petition is unlikely to be rejected.

It is also worth remembering that the Respondent (the person receiving the divorce petition) will read the reasons and this may add to or cause more distress. 

The best practice is to send to the Respondent the allegations of unreasonable behaviour reasons prior to filing the petition at court, to see whether the content can be agreed,  however, this is not always a viable option. 

Unlike adultery, the Respondent does not have to admit the behaviour or accept that it is unreasonable, but can simply choose not to defend the petition. A solicitor or mediator can help both parties decide what to include which can help to start the process in a more constructive manner.  

What are the timescales for using unreasonable behaviour in a divorce? 

It is surprising to many but there can be time limits to using unreasonable behaviour in a divorce. 

You can only file for a divorce petition based on the grounds of unreasonable behaviour after a minimum of 12 months of marriage.  

If you continue to live together after the last incident of behaviour or after the petition has been issued and for more than 6 months, the Court may ask for some more details about your living arrangements when you apply for decree nisi, as the Judge will want to be satisfied that the marriage has irretrievably broken down. 

Does unreasonable behaviour affect the final settlement? 

Some people believe that behaviours will affect how the financial assets of the marriage will be split, however, this is rarely the case. Generally, grounds for divorce are considered to be irrelevant when it comes to financial settlements. 

The need for a no-fault divorce system*

The current use of unreasonable behaviour in divorce petitions has been questioned.  Most family lawyers feel that the law needs to move on and that by forcing allegations and ascribing blame for the breakdown of the marriage introduces unnecessary or additional animosity. This makes it less likely that the parties will be able to agree on other arrangements for any dependent children and a financial settlement. 

With the likely introduction of no-fault divorce (part of the Divorce, Dissolution and Separation 2020 currently in parliament – you can track its progress here) hopefully we will see an end to the ‘blame’ game and help couples to divorce more amicably without accusations. 

Get in touch 

If you would like any advice on divorce you can visit our divorce guide page or please do contact our Client Care Team to speak to one of our specialist divorce lawyers here. 

The article was published earlier and has since been updated. 

Rachel has been with the firm for over 17 years and as Regional Director heads up the Yorkshire team across Beverley, Harrogate, Huddersfield, Ilkley, Leeds, Sheffield, Wetherbyand York. Known for her caring and compassionate approach, she builds an excellent rapport with clients, leaving them feeling confident and reassured as she guides them to the right outcome for them.

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  1. Andy says:

    It’s not unreasonable behaviour that’s is a cause more like domestic violence that is the cause and such actions conducted by either party in there quest to destroy the other party either by physical,mental and childish actions that one party will break and lash out….
    Typically the courts see all the types but in such cases the mother uses the system to benefit the accusation of what she wants to gain.

    So the three causes are used as available. Most cases are adultery as this is the easiest option to go for as proving unreasonable behaviour are difficult…desertion as stated…
    The effect of this is the easiest option to go for and set the wheel in motion to end the marriage as soon as possible..with high costs…and that is for the start.

    • Dr Grumpy says:

      I only discovered my ex wife’s infidelity with another woman several years after the absolute was granted. And we had been married for only 3 years before she did this!

  2. Dr Grumpy says:

    Of course allegations of unreasonable behaviour are just that, allegations. No witnesses required to support the petitioners claim. And lets be completely honest mud sticks!
    Allegations of domestic violence made in a divorce petition need no supporting evidence and it would appear that the courts require none.
    As a result of this I have been branded as man who inflicted DV on his ex wife. My friends and those close to me know that I would not behave in that way. As for unreasonable behaviour the petitioner is often the guilty party and uses the allegation in the petition to cover up their own actions during the marriage!

  3. Royce says:

    Reading the blog entry, I was thinking the very same thing as “Dr Grumpy” wrote, above:

    “As for unreasonable behaviour, the petitioner is often the guilty party [but] uses the [scurrilous] allegation in the petition to cover up their own [despicable] actions during the marriage!”

    Yes, this was precisely the situation in my case — my ex claimed “unreasonable behaviour”. Specifically that I tried to “control” her, when it was SHE who quite clearly was being unfaithful to me! So, my suspicions and complaints (because, with all her excuses, I could never be quite sure — till afterwards) were me “controlling” her — when obviously NO man would just sit there and eat sh+t!

    It is disgusting that this can be asserted — and no explanation ever gets a chance to be heard. Not that it makes a lot of difference, as you are still going to get a divorce — and the court isn’t interested, anyway

    The reality of course was that SHE was behaving unreasonably. And the only way to combat that (FWIW) is to get your crack in first — and start the divorce before SHE does. At least the inherent bias towards women (especially with a female judge) might be overcome to some extent — and perhaps not QUITE so much will be awarded to the unfaithful wife.

    Who, if she precipitated the divorce by her infidelity, clearly doesn’t deserve a penny — at least, in most fair-minded people’s minds.

    Seems to me that, “In order to be satisfied that the marriage has irretrievably broken down” the judge should consider just as much that the party making the allegation may be the GUILTY party — because they could well be LYING. What does it matter? See above….

  4. Reddit Seenit Dunit says:

    As Andy indicated above, some wives “just use the system to benefit the accusation of what she wants to gain….” — ie. they just play the system for their advantage. Certainly my ex did.

    Because, as I realised towards the end, it was NOT a simple, “honest” marriage, which “sadly broke down”. It was a DIShonest marriage that she craftily ENGINEERED to break down. It had, to coin a phrase that was current a few years ago, “built-in obsolescence” — it was MADE (by her) to break down in as short a time as she thought she could get away with, consistent with obtaining a big handout from the judge.

    Seeing as it is inevitably the woman who gets the “settlement”, and the man who has to pay, these sort of cynical women are clearly just playing the system — and there has been little or no attempt to STOP this practice. Has no one in the legal profession or legislature ever heard of the word, “scammer”?

    They most certainly haven — and as long as they allow this situation to continue, they are AIDING and ABETTING them.

  5. Pete says:

    “That may not be how Parliament intended the law to operate, ”
    Is it not down to the Judges to interpret the law John ?? Funny how in the example above its always the man that is to blame , yet another shining display of the legal professions bias.
    Even my own solicitor had me give in to the accusation of unreasonable behaviour saying it didn’t mean anything. but I must say I was guilty of working to keep a roof over our heads, paying for her holidays, keeping the kids in food and clothes while she collected loyalty stickers in the local coffee shops.
    Its all very well lawyers protesting for a no fault divorce but this is a mess of there own making and they should take a long look in the mirror before pointing the finger of blame at anyone !

  6. JamesB says:

    I agree with all of the above. Especially the point about the dishonest party getting the innocent party labelled bad.

    Also, the timescales are bad and the petitioner has thought things through and the respondent hasn’t.

    The only way around fault is to write own marriage vows cheaply, i.e. pre and post nups mandatory and legally enforeable for all, like in France.

    All this UB is utter ballderdash.

    Like that guy (Evans was it?) most of them are entirely without substance for a lifestyle change for women to chuck out men to get new one in and more dual income streams. Rewarding this behavious is bad. Also adding insult to injury that respondent is expected to pay costs, then you have the changing of the locks and denying contact as the money on divorce goes to kids and woman claiming status quo. No wonder marriage rates are falling with this bad law. Add to that the CSA. You dont reward a burglar for stealing your stuff. Makes no sense. That’s no fault divorce for you (well divorce on demand without pre and post nups if you are pedantic). Why is it so? Establishment stitch up and lawyers fees.

    Thing is you would get more lawyers fees with cheap pre and post nups and a better society that way anyway. Why is it so then? Ignorance of politicians and lawyers and law of unintended consequences and like queen victoria not believing in lesbians, lawyers doing the man bad woman good nonsence. Straying so far in their bubble from nautral law as to make sharia law and beth din seem more apetising. Immigrants thriving as we try to stick to dodgy laws. Overdue reform I agree with the author on that. However, not on doing it without changing financial remedies, so another reason we are stuck as government trying not to make things worse – which this undoubtably will withou AR reform as will turn even more young men into slaves or away from marriage. Follow all that lawyers? Nah, I doubt it, too busy arguing over chairs on the titanic.

    The law pushing this stuff? Well, it very much brings itself into disrepute, especially when combined with CMEC / CMS / CSA / CMOptions / whatever they are called these days.

    Has government intervention into family law made things better over the last 50 years? On the balance of probability ptobably not. Increases property prices and number of blocks of single dwelling grumpy people also.

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