Since the two seminal decisions of the House of Lords, first in White v White [2000] 2 FLR 981 and then in Miller v Miller; McFarlane v McFarlane [2006] 1 FLR 1186, introduced practitioners to the potentially crucial distinction (in sharing cases, at least) between matrimonial and non-matrimonial property, and the decision of Nicholas Mostyn QC (as he then was) in GW v RW (Financial Provision: Departure from Equality) [2003] 2 FLR 108 introduced into orthodoxy the practice of treating seamless pre-marital cohabitation as, or at least as if it were, part of a marriage, the question of when parties commenced cohabitation has assumed an important significance (although, unlike the ES1, Form E still does not require them to set out when they say that was), alongside the question of when they separated.

Consequently, nowadays, when a court finds itself considering questions of cohabitation, it is far more likely to be considering when the parties began cohabiting with one another, prior to their marriage, than whether they are or are not now cohabiting, post-separation, with a third party (which was more often the point in issue between the parties in the past, notwithstanding that, except in rare cases, that question was very often of far greater interest to one or other of them than it was to the court).

There is much jurisprudence on what amounts to cohabitation. Where cohabitation with a third party is concerned, the case most often referred to (although almost certainly not the leading authority, properly-so-called, given that it was decided at Circuit Judge level) is probably still Kimber v Kimber [2000] 1 FLR 383, which highlighted (i) living together in the same household; (ii) a sharing of daily life; (iii) stability and permanence; (iv) a mingling of finances; (v) a sexual relationship; (vi) a relationship with each other’s children; (vii) a couple’s intentions and motivations; and (viii) the opinion of the reasonable person with normal perceptions, as being amongst the potentially relevant considerations.

In this context, honourable mentions must also go to the decisions of Coleridge J in K v K (Periodical Payments: Cohabitation) [2006] 2 FLR 468, the Court of Appeal in Grey v Grey [2010] 1 FLR 1764, and His Honour Judge Willans in KG v NB [2023] EWFC 160 (B), in which case it was observed, at [23], that ‘an issue such as cohabitation is dynamic rather than static in character’ and ‘[r]elationships can of course wax and wane and commitment is often a developing emotion’.

Authorities dealing with the question of pre-marital cohabitation include GW v RW; McCartney v Mills McCartney [2008] 1 FLR 1508, per Bennett J; IX v IY (Financial Remedies: Unmatched Contributions) [2019] 2 FLR 449, per Williams J; E v L (Financial Remedies) [2022] 1 FLR 952, per Mostyn J; and VV v VV [2023] 1 FLR 170, per Peel J.

In IX v IY, Williams J had to consider when it might be said that a cohabiting relationship had commenced. At [68], he said as follows:

‘What the court must be looking to identify is a time at which the relationship had acquired sufficient mutuality of commitment to equate to marriage. Of course, in very many cases, possibly most cases, this will be very obviously marked by the parties’ cohabiting, possibly in conjunction with the purchase of a property. However, in other cases, and this may be one of them, it is not so easy to identify. The mere fact that parties begin to spend time in each other’s houses does not of itself, it seems to me, equate to marriage. In situations such as this the court must look at an accumulation of markers of marriage which eventually will take the relationship over the threshold into a quasi-marital relationship which may then either be added to the marriage to establish a longer marriage or becomes a weightier factor as one of the circumstances of the case.’

There is far less authority on what amounts to separation. In FT v JT [2023] EWFC 250 (B), Recorder Nicholas Allen KC stated, at [39], that ‘in many senses it is the obverse of cohabitation’. In MB v EB (Preliminary Issues in Financial Remedy Proceedings) [2019] 2 FLR 899, Cohen J cited paragraph [68] of IX v IY, before stating, at [51], that ‘[t]hat analysis can be applied to an attempt to define the date of the end of the marriage as much to its commencement’. Thereafter he observed, at [52] and [54]:

‘It is a truism that marriages come in all different shapes and sizes. What may be important to one couple may be trivial to another … In some rare cases the definition of when parties separated can be extremely difficult. This is one such case. In most cases it is clear when one, if not both parties, to a marriage emotionally and physically disconnect from it.’

In B v S (Financial Remedy: Marital Property Regime) [2012] 2 FLR 502, Mostyn J had to determine the date of the parties’ separation. He observed that it was ‘invidious to try to anatomise a marriage by reference to the contentedness of the parties in order to attribute an arbitrary date to its ending’, and concluded that the parties ‘were certainly not separated in the Santos v Santos [1972] Fam 247 sense’ at the date alleged by the husband to have been the effective date of separation.

That was a reference to the decision of Sachs LJ in Santos v Santos, where, at p.263, the court was considering the meaning of the words ‘living apart’ in the Divorce Reform Act 1969, re-enacted in the Matrimonial Causes Act 1973 s 1(6) – in other words what was required to establish that the parties had been living apart for the purposes of the five year separation period. It was held that the relevant state of affairs did not exist:

‘while both parties recognise the marriage as subsisting. That involves considering attitudes of mind; and naturally the difficulty of judicially determining that attitude in a particular case may on occasions be great.’

In other words, one or the other, or both, of the parties had to cease to recognise the marriage as subsisting for the state of affairs to exist.

In VV v VV, after referring to the other authorities in relation to cohabitation and after stating, at [44], that he agreed with the view expressed by Mostyn J in E v L (Financial Remedies), at [28], that ‘it is dangerous for the court to evaluate the quality of a marriage’, at [45] and [46], Peel J stated:

’To the above jurisprudence I would add that the court should also look at the parties' respective intentions when inquiring into cohabitation. Where one or both parties do not think they are in a quasi-marital arrangement, or are equivocal about it, that may weaken the cohabitation case. Where, by contrast, they both consider themselves to be in a quasi-marital arrangement, that is likely to strengthen the cohabitation case … In the end, it is a fact-specific inquiry. Human relationships are varied and complex; they do not easily lend themselves to pigeon holing. The essential inquiry is whether the pre-marital relationship is of such a nature as to be treated as akin to marriage.’

In MR v EF [2024] EWFC 144 (B), Recorder Taylor observed, at [60], that by these comments Peel J ‘appears to advocate a subjective element to the analysis’. At [61], he stated that the subjective element was touched upon again in DE v FE [2022] EWFC 71, by Sir Jonathan Cohen, at [20]:

‘I am not impressed by H’s argument that W’s answer to the question in her divorce petition of when they separated as being November 2017 is conclusive of the point. Whilst that date marks the physical separation it was not the date of their emotional separation nor the date when, as I find, either had concluded that the marriage was at an end. I suspect that as 2018 went on H became less optimistic for the future of the marriage whilst W remained more hopeful.’

At [62] and [63], Recorder Taylor continued as follows:

‘The subjective element of gazing through the window, into the heart of a marriage, was deprecated by King LJ in Cazalet v Abu-Zalaf [2023] EWCA Civ 1065, [2024] 1 FLR 565 where one of the questions concerned whether the parties had reconciled during the course of proceedings, such that the decree nisi should be rescinded … At [73(i)] King LJ commented that the judge’s evaluation was undermined by:

“The introduction of his own assessment of the quality of the relationship of the parties and his personal view as to the essential components of a marriage. The judge fell into this error notwithstanding that he had specifically reminded himself, by reference to his own decision in NB v MI (Capacity to Contract Marriage) [2021] EWHC 2249 (Fam), [2021] 2 FLR 786, that ‘marriages come in all shapes and sizes’ and that a marriage ‘does not require the parties to love one another’. In the present case, the judge instead went on at para [46] to say that ‘It does require, however, that the parties recognise that they enjoy a particular status and that they are in a formal union of mutual and reciprocal expectations of which the foremost is the sharing of each other’s society, comfort and assistance’.”’

Those comments echo those of Sir James Munby P, in Re X (A Child – Foreign Surrogacy) [2018] 2 FLR 660, at [7], that a ‘marriage is a marriage’. That observation was cited in E v L (Financial Remedies), at [29], where Mostyn J said that for the court to start asking why there are no children and whether this denotes a lesser extent of commitment to the relationship ‘is to make windows into people’s souls, and should be avoided at all costs’.

Recorder Taylor then observed, at [64], that:

'there are conflicting cases about the applicability of the subjective element to determining whether parties consider themselves to be in a marital or quasi-marital relationship. This apparent conflict is made more difficult when the same question is being asked in slightly differing contexts.'

Having then considered that it did not fall to him to resolve these apparent conflicts he stated, at [65]:

‘For my purposes, I am going to apply the non-subjective approach of King LJ. I am looking at objective and external markers. Cazalet v Abu-Zalaf is the more recent and more authoritative statement. Even if I am wrong to do so, I am fortified in this case that there is a solid mass of objective evidence which allows me to make my determinations without having to subjectively try to peer into the parties’ souls.’

Perhaps unsurprisingly, and certainly unhelpfully, there are live issues as to whether the authorities on cohabitation and separation are consistent, within their respective groups and across them both, as to whether the test to be applied is subjective or objective. Interestingly, of course, the non-exhaustive list of potentially relevant considerations proffered by His Honour Judge Tyrer in Kimber v Kimber, derived from earlier authorities and the Social Security Contributions and Benefits Act 1992, involved both: the couple’s subjective intentions and motivations and the objective assessment of the reasonable person with normal perceptions (nowadays not necessarily either a man or aboard the Clapham Omnibus).