Bellinger v Bellinger  UKHL 21;  2 AC 467;  2 All ER 593
LORD NICHOLLS OF BIRKENHEAD:
 My Lords, can a person change the sex with which he or she is born? Stated in an over-simplified and question-begging form, this is the issue raised by this appeal. More specifically, the question is whether the petitioner, Mrs Elizabeth Bellinger, is validly married to Mr Michael Bellinger. On 2 May 1981 Mr and Mrs Bellinger went through a ceremony of marriage to each other. Section 1(c) of the Nullity of Marriage Act 1971, re-enacted in s 11(c) of the Matrimonial Causes Act 1973, provides that a marriage is void unless the parties are 'respectively male and female'. The question is whether, at the time of the marriage, Mrs Bellinger was 'female' within the meaning of that expression in the statute. In these proceedings she seeks a declaration that the marriage was valid at its inception and is subsisting. The trial judge, Johnson J, refused to make this declaration: see  3 FCR 733. So did the Court of Appeal, by a majority of two to one: see  2 WLR 411. The majority comprised Dame Elizabeth Butler-Sloss P and Robert Walker LJ. Thorpe LJ dissented.
 In an alternative claim, advanced for the first time before your Lordships' House, Mrs Bellinger seeks a declaration that s 11(c) of the 1973 Act is incompatible with arts 8 and 12 of the European Convention.....
 Mrs Bellinger was born on 7 September 1946. At birth she was correctly classified and registered as male. That is common ground. For as long as she can remember, she felt more inclined to be female. She had an increasing urge to live as a woman rather than as a man. Despite her inclinations, and under some pressure, in 1967 she married a woman. She was then 21. The marriage broke down. They separated in 1971 and were divorced in 1975.
 Since then Mrs Bellinger has dressed and lived as a woman. She underwent treatment, described below. When she married Mr Bellinger he was fully aware of her background. He has throughout been entirely supportive of her. She was described on her marriage certificate as a spinster. Apart from that, the registrar did not ask about her gender status, nor did Mrs Bellinger volunteer any information. Since their marriage Mr and Mrs Bellinger have lived happily together as husband and wife, and have presented themselves in this way to the outside world.
THE INDICIA OF SEX AND TRANSSEXUAL PEOPLE
 The indicia of human sex or gender (for present purposes the two terms are interchangeable) can be listed, in no particular order, as follows. (1) Chromosomes: XY pattern in males, XX in females. (2) Gonads: testes in males, ovaries in females. (3) Internal sex organs other than the gonads: for instance, sperm ducts in males, uterus in females. (4) External genitalia. (5) Hormonal patterns and secondary sexual characteristics, such as facial hair and body shape: no one suggests these criteria should be a primary factor in assigning sex. (6) Style of upbringing and living. (7) Self-perception. Some medical research has suggested that this factor is not exclusively psychological. Rather, it is associated with biological differentiation within the brain. The research has been very limited, and in the present state of neuroscience the existence of such an association remains speculative.
 In the vast majority of cases these indicia in an individual all point in the same direction. There is no difficulty in assigning male or female gender to the individual. But nature does not draw straight lines. Some people have the misfortune to be born with physiological characteristics which deviate from the normal in one or more respects, and to lesser or greater extent. These people attract the convenient shorthand description of inter-sexual. In such cases classification of the individual as male or female is best done by having regard to all the factors I have listed. If every person has to be classified as either male or female, that is the best that can be done. That was the course, in line with medical opinion, followed by Charles J in W v W (nullity)  3 FCR 748 at 787; sub nom W v W (physical inter-sex)  Fam 111 at 146. That is not the problem arising in the present case.
 Transsexual people are to be distinguished from inter-sexual people. Transsexual is the label given, not altogether happily, to a person who has the misfortune to be born with physical characteristics which are congruent but whose self-belief is incongruent. Transsexual people are born with the anatomy of a person of one sex but with an unshakeable belief or feeling that they are persons of the opposite sex. They experience themselves as being of the opposite sex. Mrs Bellinger is such a person. The aetiology of this condition remains uncertain. It is now generally recognised as a psychiatric disorder, often known as gender dysphoria or gender identity disorder. It can result in acute psychological distress.
 The treatment of this condition depends upon its severity and the circumstances of the individual. In severe cases conventional psychiatric treatment is inadequate. Ultimately the most that medical science can do in order to alleviate the condition is, in appropriate cases, to rid the body of its intensely disliked features and make it accord, so far as possible, with the anatomy craved. This is done by means of hormonal and other treatment and major surgery, popularly known as a 'sex change' operation. In this regard medical science and surgical expertise have advanced much in recent years. Hormonal treatment can change a person's secondary sexual characteristics. Irreversible surgery can adapt or remove genitalia and other organs, external and internal. By this means a normal body of one sex can be altered so as to give the appearance of a normal body of the other sex. But there are still limits to what can be done. Gonads cannot be constructed. The creation of replica genital organs is particularly difficult with female-to-male gender reassignment surgery. Chromosomal patterns remain unchanged. The change of body can never be complete.
 Surgery of this nature is the last step in what are typically four steps of treatment. The four steps are psychiatric assessment, hormonal treatment, a period of living as a member of the opposite sex subject to professional supervision and therapy (the 'real life experience'), and finally, in suitable cases, gender reassignment surgery. In February 1981 Mrs Bellinger, having been through the previous stages of treatment, successfully underwent this form of surgery....
THE PRESENT STATE OF THE LAW
 The present state of English law regarding the sex of transsexual people is represented by the well-known decision of Ormrod J in Corbett v Corbett (orse Ashley)  2 All ER 33 at 47, 48,  P 83 at 104, 106. That case, like the present one, concerned the gender of a male-to-female transsexual in the context of the validity of a marriage. Ormrod J held that, in this context, the law should adopt the chromosomal, gonadal and genital tests. If all three are congruent, that should determine a person's sex for the purpose of marriage. Any operative intervention should be ignored. The biological sexual constitution of an individual is fixed at birth, at the latest, and cannot be changed either by the natural development of organs of the opposite sex or by medical or surgical means....
THE EUROPEAN COURT OF HUMAN RIGHTS
 This issue has been before the European Court of Human Rights on several occasions in the last 20 years. During this period the development of human rights law on this issue has been remarkably rapid. Until very recently the court consistently held that application of the Corbett criteria, and consequent non-recognition of change of gender by post-operative transsexual persons, did not constitute a violation of art 8 (right to respect for private life) or art 12 (right to marry): Rees v UK (1986) 9 EHRR 56, Cossey v UK  2 FCR 97 and Sheffield and Horsham v UK  3 FCR 141. It is to be noted, however, that in the latter case the court was critical of the United Kingdom's apparent failure to take any steps to keep this area of the law under review. There is, the court said, an increased social acceptance of transsexualism and an increased recognition of the problems which post-operative transsexual people encounter. The court reiterated that this area 'needs to be kept under review by contracting states' (see  3 FCR 141 at 157 (para 60)).
 In its most recent decision the court has taken the view that the sands of time have run out. The United Kingdom's margin of appreciation no longer extends to declining to give legal recognition to all cases of gender reassignment. This was the decision of the court, sitting as a grand chamber, in the case of Goodwin v UK  2 FCR 577. Judgment was given in July 2002, that is, after the Court of Appeal gave its judgment in the present case. Christine Goodwin was a post-operative male-to-female transsexual. The court held unanimously that the United Kingdom was in breach of arts 8 and 12.
 The court's judgment was wide-ranging. As it happens, this was not a 'marriage' case. Christine Goodwin had married as a man and later been divorced. Her complaint was that in several respects she, as a post-operative transsexual person, was not treated fairly by the laws or practices of this country. She was unable to pursue a claim for sexual harassment in an employment tribunal because she was considered in law to be a man. She was not eligible for a state pension at 60, the age of entitlement for women. She remained obliged to pay the higher car insurance premiums applicable to men. In many instances she had to choose between revealing her birth certificate and foregoing advantages conditional upon her producing her birth certificate. Her inability to marry as a woman seems not to have been the subject of specific complaint by her. But in its judgment the court expressed its views on this and other aspects of the lack of legal recognition of her gender reassignment.
 Some of the main points in the judgment of the court can be summarised as follows. In the interests of legal certainty, foreseeability and equality before the law the court should not depart, without good reason, from precedents laid down in previous cases. But the court must have regard to changing conditions within the respondent state and within contracting states generally. The court must respond to any evolving convergence on the standards to be achieved (see  2 FCR 577 at 598 (para 74)). A test of congruent biological factors can no longer be decisive in denying legal recognition to the change of gender of a post-operative transsexual (at 605 (para 100)). With increasingly sophisticated types of surgery and hormonal treatments the principal unchanging biological aspect of gender identity is the chromosomal element. It is not apparent that this must inevitably be of decisive significance (at 600 (para 82)). The court recognised that it is for a contracting state to determine, amongst other matters, the conditions under which a person claiming legal recognition as a transsexual establishes that gender reassignment has been properly effected. But it found (at 606 (para 103)) 'no justification for barring the transsexual from enjoying the right to marry under any circumstances'.
 This decision of the court was essentially prospective in character. The court made this plain. Until 1998, the date of the decision in Sheffield and Horsham v UK, the court had found that the United Kingdom's treatment of post-operative transsexual people was within this country's margin of appreciation and that this treatment did not violate the convention. By the Goodwin v UK decision the court found that 'the situation, as it has evolved, no longer falls within the United Kingdom's margin of appreciation' (see  2 FCR 577 at 608-609 (paras 119-120); emphasis added).
DEVELOPMENTS SINCE GOODWIN v UK
 This decision of the European Court of Human Rights prompted three developments. First, in written answers to the House of Commons on 23 July 2002, the Parliamentary Secretary to the Lord Chancellor's Department noted that the interdepartmental working group on transsexual people had been reconvened. Its terms of reference include re-examining the implications of granting full legal status to transsexual people in their acquired gender. The minister stated that the working group had been asked to consider urgently the implications of Goodwin v UK.
 The second development has an important bearing on the outcome of this appeal. On 13 December 2002 the government announced its intention to bring forward primary legislation which will allow transsexual people who can demonstrate they have taken decisive steps towards living fully and permanently in the acquired gender to marry in that gender. The legislation will also deal with other issues arising from the legal recognition of acquired gender. A draft outline Bill will be published in due course.
 The third development was that before your Lordships' House counsel for the Lord Chancellor accepted that, from the time of Goodwin v UK, those parts of English law which fail to give legal recognition to the acquired gender of transsexual persons are in principle incompatible with arts 8 and 12 of the convention. Domestic law, including s 11(c) of the Matrimonial Causes Act 1973, will have to change....
GENDER AND MARRIAGE: PART OF A WIDER PROBLEM
 My Lords, I am profoundly conscious of the humanitarian considerations underlying Mrs Bellinger's claim. Much suffering is involved for those afflicted with gender identity disorder. Mrs Bellinger and others similarly placed do not undergo prolonged and painful surgery unless their turmoil is such that they cannot otherwise live with themselves. Non-recognition of their reassigned gender can cause them acute distress. I have this very much in mind....
 Despite this, I am firmly of the view that your Lordships' House, sitting in its judicial capacity, ought not to accede to the submissions made on behalf of Mrs Bellinger. Recognition of Mrs Bellinger as female for the purposes of s 11(c) of the 1973 Act would necessitate giving the expressions 'male' and 'female' in that Act a novel, extended meaning: that a person may be born with one sex but later become, or become regarded as, a person of the opposite sex.
 This would represent a major change in the law, having far-reaching ramifications. It raises issues whose solution calls for extensive inquiry and the widest public consultation and discussion. Questions of social policy and administrative feasibility arise at several points, and their interaction has to be evaluated and balanced. The issues are altogether ill-suited for determination by courts and court procedures. They are pre-eminently a matter for Parliament....
 [T]he recognition of gender reassignment for the purposes of marriage is part of a wider problem which should be considered as a whole and not dealt with in a piecemeal fashion. There should be a clear, coherent policy. The decision regarding recognition of gender reassignment for the purpose of marriage cannot sensibly be made in isolation from a decision on the like problem in other areas where a distinction is drawn between people on the basis of gender. These areas include education, child care, occupational qualifications, criminal law (gender-specific offences), prison regulations, sport, the needs of decency and birth certificates. Birth certificates, indeed, are one of the matters of most concern to transsexual people, because birth certificates are frequently required as proof of identity or age or place of birth. When, and in what circumstances, should these certificates be capable of being reissued in a revised form which does not disclose that the person has undergone gender reassignment?....
DECLARATION OF INCOMPATIBILITY
 Mrs Bellinger advanced a further, alternative claim for a declaration that in so far as s 11(c) of the 1973 Act makes no provision for the recognition of gender reassignment it is incompatible with arts 8 and 12 of the convention. Her claim is advanced on the footing that, although she and Mr Bellinger celebrated their marriage long before the 1998 Act came into force, and although Goodwin v UK dealt with the human rights position as at the date of the judgment (July 2002), the non-recognition of their ability to marry continues to have adverse practical effects. The statute continues to prevent them marrying each other.
 Mr Sales advanced several arguments on why such a declaration should not be made. There is, he submitted, no present incompatibility between the statute and the convention. The European Court of Human Rights, in its decision in Goodwin v UK, envisaged that the government should have a reasonable period in which to amend domestic law on a principled and coherent basis. The court said it 'will be for the United Kingdom Government in due course to implement such measures as it considers appropriate to fulfil its obligations': see  2 FCR 577 at 608 (para 120); emphasis added.
 I cannot accept this submission. It may be that, echoing the language of the European Court of Human Rights in Marckx v Belgium (1979) 2 EHRR 330 at 353 (para 58) the principle of legal certainty dispenses the United Kingdom government from re-opening legal acts or situations which antedate the judgment in Goodwin v UK. But that is not the present case. In the present case s 11(c) of the 1973 Act remains a continuing obstacle to Mr and Mrs Bellinger marrying each other....
[  Then Mr Sales submitted that a declaration of incompatibility would serve no useful purpose. A declaration of incompatibility triggers the ministerial powers to amend the offending legislation under the 'fast track' procedures set out in s 10 and Sch 2 to the 1998 Act. But the minister's powers have already been triggered in the present case under s 10(1)(b), by reason of the decisions of the European Court of Human Rights in Goodwin v UK and the associated case of I v UK  2 FCR 613. Further, the government has already announced its intention to bring forward primary legislation on this subject. For this reason also, counsel submitted, making a declaration of incompatibility would serve no useful purpose.
 I am not persuaded by these submissions. If a provision of primary legislation is shown to be incompatible with a convention right the court, in the exercise of its discretion, may make a declaration of incompatibility under s 4 of the 1998 Act. In exercising this discretion the court will have regard to all the circumstances. In the present case the government has not sought to question the decision of the European Court of Human Rights in Goodwin v UK. Indeed, it is committed to giving effect to that decision. Nevertheless, when proceedings are already before the House, it is desirable that in a case of such sensitivity this House, as the court of final appeal in this country, should formally record that the present state of statute law is incompatible with the convention. I would therefore make a declaration of incompatibility as sought. I would otherwise dismiss this appeal.