Under Article 12 of the European Convention of Human Rights, men and women of marriageable age have the right to marry. However, this right is expressed as being subject to "the national laws governing the exercise of this right".

Essentially, the starting point is that everyone has a right to marry in accordance with the limitations of the legal frameworks.

In England, the Courts have indicated that the only kind of marriage which English law recognises is one which is essentially the voluntary union for life of one man with one woman to the exclusion of all others (1).  A civil partnership is a relationship between, and affording the same legal status and rights as a married couple to, two people of the same sex which is formed when they register as civil partners of each other (2).  For ease of reference, I will use the term “marriage” to mean marriage or civil partnership for the remainder of this article.

Pre-requisites for valid marriage

The pre-requisites for a valid marriage and a valid civil partnership are set out over a number of statutes and through various case law but can be reduced to the following principles:

  • that each of the parties should as regards age and mental and physical capacity be capable of contracting marriage
  • that they should not by reason of kindred or affinity be prohibited from marrying one another (i.e. too close a relationship)
  • that, except where a second or subsequent polygamous marriage has been entered into under a law that permits polygamy, there should not be a valid subsisting marriage or civil partnership of either of the parties with any other person
  • that the parties, understanding the nature of the contract, should freely consent to marry one another; and
  • that certain forms and ceremonies should be observed

This article will focus on the first pre-requisite, and in particular, the requisite mental capacity to enter into a valid marriage. More frequently, healthcare professionals are asked to report upon a person’s capacity to enter into a marriage.

Impact of capacity and mental disorder on marriage

For the purposes of a healthcare professional being asked to assess whether a person has capacity to marry, there are three fundamental issues:

  1. Does the person have capacity to consent to marriage?
  2. Is the person free from duress or coercion in making that decision?
  3. Does the person suffer from a mental disorder which renders them “unfit” for marriage?

The burden of proof in demonstrating that a person either lacks capacity to consent to marriage, or is suffering from a mental disorder so as to be unfit for marriage, is on the person putting that position forwards.

It is worth highlighting that these issues render a marriage voidable, rather than void. In other words, even if a person lacks capacity, or is unduly influenced or has a mental disorder rendering them unfit for marriage, this will not automatically render the marriage void, but instead will give either party to the marriage the right to petition the Court for a decree of nullity (3).

Capacity to consent to marriage

The key here, is that the test is whether the person has capacity to consent to marriage generally, not whether they have capacity to consent to marriage to a particular person. In addition, there is a low threshold for capacity to consent to marriage. The contract of marriage and its concept, are considered, in essence to be a simple one that it will not require a high degree of intelligence to comprehend.

Since October 2007, the statutory test for determining capacity has been laid down in the Mental Capacity Act 2005 (the “Act”). Capacity is decision and time specific. There is a two-part test (4) and in this respect the relevant assessment is whether the person has the capacity to consent to marriage:

  1. Is there an impairment of or disturbance in the functioning of the person's mind or brain?
  2. Does that impairment or disturbance mean that they are able to consent to marriage? In determining this, can the person:
  • Understand the information relevant to that decision?
  • Retain that relevant information? (Can the person hold the information in her mind long enough to use it to make an effective decision?)
  • Use or weigh that relevant information as part of the process of making the decision (sometimes people can understand information but an impairment or disturbance affects their ability to weigh up the options available and their risks/benefits)?
  • Communicate their decision?
    In assessing capacity, all reasonable steps to facilitate the person having capacity should be taken.

Things to consider include:

  • Is there a particular professional that the person has a good therapeutic relationship with who may be best placed to provide the person with the relevant information?
  • Is there a particular time of day when the person is most likely to have capacity?
  • Are there particular locations which may make the person feel more comfortable?
  • Is there a particular third party who could support the person during the assessment?

Where a person lacks capacity around marriage, no one is permitted to make a decision in their best interests to consent to a marriage.

“Relevant information” for marriage

The Courts are clear that the crux of this issue is whether the person is able to understand the nature of the contract of marriage. That includes understanding the duties and responsibilities normally attached to a marriage:

  • Live together and love one another to the exclusion of all others
  • Share a common home and domestic life
  • Right to enjoy each other’s society, comfort and assistance
  • Implicit that it includes a sexual relationship

It is clear that it is not enough that someone appreciates that he or she is taking part in a marriage ceremony or understands its words.

The following considerations are irrelevant for the purpose of assessing capacity to consent to marriage:

  • Whether it is a wise decision for the person to marry (a) at all and (b) the particular fiancé(e)
  • The ability to understand or evaluate the characteristics of a particular fiancé(e)
  • The ability to understand the implications (emotional, social, financial and other) of a particular marriage (5)

It follows, therefore, that generally speaking, in order to have capacity to consent to marriage a person must have capacity to consent to sexual relations. As with capacity for marriage, capacity to consent to sexual relations is directed to the nature of the activity rather than to the identity of the sexual partner.

The relevant information that they need to understand to have such capacity in relation to sexual relations is:

  • Nature and character of the act of sexual intercourse (the understanding need not be sophisticated, simply the mechanics and the fact that the act is of  sexual nature)
  • Reasonably foreseeable consequences of sexual intercourse (e.g. pregnancy and STIs – it is only necessary to understand the proximate consequences of intercourse, not necessarily the emotional, moral or less direct consequences)
  • Ability to choose whether or not to engage in sexual intercourse (6)

Ability to weigh or use the relevant information

If, due to the person’s disturbance or impairment in the functioning of the mind or brain, in certain situations they are unable to weigh up and use the relevant information, they will lack capacity. For example, where a patient has a learning disability which is associated with suggestibility and a tendency to acquiescence, they may understand all of the Relevant Information but be unable to weigh it in the balance when in the presence of the particular partner due to the coercive nature of the partner’s actions.

Duress and coercion

A person may have capacity to consent to marriage and sexual relations, but not be able to provide valid consent because of duress or coercion. This will be person and situational specific.

The case law (7) around undue influence suggests that this amounts to unacceptable forms of persuasion. However, the cases do not define this concept in more than a broad manner, setting out two categories:

  1. Overt Actions - blatant forms of physical coercion, such as personal violence, and acts of improper pressure or coercion such as unlawful threats; and
  2. Relationship - arising out of a relationship between two persons where one has acquired over another a measure of influence, or ascendancy, of which the ascendant person then takes unfair advantage - the relationship between two individuals may be such that one of them is disposed to agree a course of action proposed by the other - the question is whether one party has reposed sufficient trust and confidence in the other, rather than whether the relationship between the parties belongs to a particular type

Mental disorder

This is where, though capable of giving a valid consent, the person is suffering (whether continuously or intermittently) from mental disorder within the meaning of Mental Health Act 1983 of such a kind or to such an extent as to be “unfitted” for marriage.

The Courts have indicated that to determine if a person is “unfitted” for marriage, the relevant question is; “Is this person capable of living in a married state, and of carrying out the ordinary duties and obligations of marriage”  by reason of that mental disorder?

The Judge indicated the high threshold that would be required for a person to be “unfitted” for marriage by reason of mental disorder when he said:

“It can only be those unfortunate people who suffer from a really serious mental disorder who can positively be stated in humane terms to be incapable of marriage.”

In reality, due to the very high threshold required to void a marriage on the basis that one party was unfit for marriage by way of mental disorder; healthcare professionals are far more likely to be asked to assess a persons capacity to provide valid consent to marriage.

When should an assessment be conducted?

A person has to have the capacity to consent to marriage, be free from undue influence and not have a mental disorder rendering them unfit for marriage at the time of the marriage.

However, to enable practical arrangements for a marriage to be made, it is suggested that the assessment should be carried out some time before the marriage and then, assuming this reveals that the patient has got capacity, there should be a brief review of the questions prior to the marriage ceremony.

Practical suggestions in carrying out an assessment

Whilst the Courts have explained that it is not necessary for a person to have sought professional advice on marriage in order to have capacity, healthcare professionals may wish to involve a marriage counsellor in the assessment of capacity.

In addition, where a person’s family or carers consider that the person lacks capacity, it may be beneficial to involve them in the discussion where possible so that their concerns can be raised and addressed.

Key issues for assessments for marriage

1. Threshold for capacity is low

2. Does the person have capacity to consent to marriage?

a) Do they have a disturbance or impairment of the mind or brain?
b) Do they understand the Relevant Information for marriage and for sexual relationships (N.B. this is not dependent upon the particular fiancé(e))?
c) Can they retain that Relevant Information?
d) Can they weigh in the balance the Relevant Information (this may be impacted by their mental disorder, person specific or situation specific characteristics of the partner)?
e) Can they communicate their decision?

3. Are they able to give valid consent free from duress or coercion (person specific characteristics of the partner may impact)?

4. Do they suffer from a mental disorder (under the Mental Health Act 1983) which renders them “unfit” for marriage? (N.B. This is a very high threshold).

What steps can be taken to prevent a marriage taking place?

An application can be made to the Court of Protection for:

  • A declaration that the person lacks capacity to marry
  • Undertakings (where the person giving the undertaking has capacity to do so) from appropriate persons confirming that they will not marry the person – these can be enforced
  • A declaration that any marriage by the person will not be recognised in English law.



(1) Nachimson v Nachimson [1930] P 217, CA; Hyde v Hyde and Woodmansee (1866) LR 1 P & D 130; Re Bethell, Bethell v Hildyard (1888) 38 ChD 220; Sowa v Sowa [1961] P 70, [1961] 1 All ER 687, CA
(2) Civil Partnership Act 2004 s.1(1)
(3) Matrimonial Causes Act 1973 s.12
(4) Ss.2-3 Mental Capacity Act 2005
(5) Sheffield v E [2005] Fam 326
(6) DBC v AB [2011] 3 All ER 435 and A LA v H [2012] EWHC 49
(7) Royal Bank of Scotland v Etridge [2001] UKHL 44
(8) Bennett v Bennett [1969] 1 All ER 539, [1969] 1 WLR 430

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