The only ground for divorce in England and Wales is the irretrievable breakdown of marriage, so in order to divorce, you must prove that the marriage has broken down via one of five accepted facts – including unreasonable behaviour.

Here, legal executive and family law specialist Diane Matthews explores what unreasonable behaviour is and explains the legal requirements that must be met to rely on this fact in divorce proceedings.

Relationship breakdown

Unreasonable behaviour is one of the five accepted facts needed to prove that a marriage has broken down irretrievably. Interestingly, it isn’t the behaviour itself that must be unreasonable, but the expectation of continuing life together.

There doesn’t need to be a link between the fact and the breakdown of the marriage. The fact simply provides the evidence of the breakdown, and if the fact is established, then a presumption of irretrievable breakdown follows.

Given that unreasonable behaviour and adultery are the only two facts that allow divorce proceedings to start immediately – provided that the parties have been married for at least one year – a vast number of divorce petitions are based on these two facts.

The remaining three facts require the petitioner to wait a period of two years minimum before bringing proceedings.

What is unreasonable behaviour?

Under the Matrimonial Causes Act 1973, to establish the fact of unreasonable behaviour you must prove that your spouse has behaved in such a way that you cannot reasonably be expected to live with them. The court will:

  • Consider the behaviour allegations in the petition and establish what the respondent did and did not do
  • Assess the effect of that behaviour on this particular petitioner taking into account the latter’s personality and disposition and all of the circumstances in which it occurred
  • Evaluate whether, as a result of the behaviour and in the light of its effect, an expectation of continuing to live together is

In practice, the allegations of behaviour don’t have to be serious and most legal practitioners encourage details of behaviour to be presented in a way that will minimise acrimony between the parties. However, the mere fact that one spouse has become bored with the marriage or feels that they’re no longer compatible is insufficient.

It’s a balancing act between a divorce petition being too weak – resulting in it being rejected by the court – and it being too strong and causing the other spouse to refuse to consent to the divorce.

The Family Law Protocol which divorce specialists follow recommends only including details of behaviour that is brief but sufficient enough to satisfy the court to grant the divorce, while references to any children should not be included.

Behaviour that could be cited

The sort of behaviour which is sufficient to illustrate that a marriage or civil partnership has broken down irretrievably and could be cited within proceedings includes:

  • Verbal abuse, including insults, criticism, threats and general unpleasantness
  • Physical violence
  • Failure to provide emotional support
  • Failure to provide financial support and withholding money
  • Inappropriate, sexual demands or conversely a lack of interest in sex
  • Failure to assist with household chores
  • Failure to assist with childcare
  • Prioritising relationships with other people, including family and friends, over the spousal relationship
  • Prioritising work or hobbies over the relationship
  • Drinking to excess or taking drugs
  • Improper association with other men or women.

One party may also have left the marital home which could be included in the divorce petition.

Impact is key

It’s important to keep in mind that it’s the impact of the behaviour that is key, with details about the behavioural impacts – such as causing distress – included in a statement.

A common misconception with behaviour divorces is that the person held at fault will be penalised in any financial remedy proceedings, which only ever happens in exceptional circumstances.

Although unreasonable behaviour is one of the most commonly cited reasons for divorce, it’s also extremely complicated, therefore it’s vital for both spouses to seek professional legal advice prior to commencing divorce proceedings. This will also help avoid significant acrimony and distress between the divorcing parties.

Diane Matthews is a legal executive based at WHN’s Blackburn office who specialises in divorce and separation, including the dissolution of civil partnerships and the associated financial consequences. Diane has experience in the complexities surrounding dividing family run businesses on separation, resolving financial and property disputes for unmarried families, pre-nuptial agreements and cohabitation agreements. To contact Diane, call her on 01254 272640 or email