Bundesverfassungsgericht

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Criminal liability of sibling incest is constitutional

Press release No. 29/2008 of 13 March 2008

Order of 26 February 2008
2 BvR 392/07

The provision in § 173.2 sentence 2 of the German Criminal Code (Strafgesetzbuch, hereinafter: StGB), which threatens sexual intercourse between natural siblings with imprisonment of not more than two years or a fine, is compatible with the Basic Law. This was decided by the Second Senate of the Federal Constitutional Court. The legislature did not overstep its discretion in decision-making when it deemed protection of the family order from the damaging effects of incest, protection of the "inferior/weaker" partner in an incestuous relationship, as well as the avoidance of serious genetic diseases in children of incestuous relationships, sufficient to punish incest, which is taboo in society, through criminal law.

This made the constitutional complaint unsuccessful, which had been lodged by a complainant who had been sentenced to several terms of imprisonment for sexual intercourse with relatives pursuant to § 173.2 sentence 2 StGB.

Judge Hassemer attached a dissenting opinion to the decision. In his view, the provision is incompatible with the principle of proportionality.

In essence, the decision is based on the following considerations:

The decision of the legislature to impose criminal penalties on sibling incest, in accordance with the standard under Article 2.1 in conjunction with Article 1.1 of the Basic Law (Grundgesetz - GG; right to sexual self-determination) which are to be addressed in the first instance, are constitutionally unobjectionable.

1. With the criminal provision of § 173.2 sentence 2 StGB, the legislature restricts the right to sexual self-determination of natural siblings by making the completion of sexual intercourse between them a punishable offence. In this way the conduct of one's private life is limited, particularly in that certain forms of expressions of sexuality between persons close to one another is penalised. However, this is not an encroachment upon the core area of private life which is impermissible to the legislature from the outset. Sexual intercourse between siblings does not affect them exclusively, but rather, can have effects on the family and society and consequences for children resulting from the relationship. Because the criminal-law prohibition on incest only affects a narrowly defined behaviour and only selectively curtails possibilities for intimate communication, the parties concerned also are not placed in a hopeless position incompatible with respect for human dignity.

2. The legislature pursues objectives through the challenged provision that are not constitutionally objectionable and, in any event, in their totality legitimise the limitation on the right to sexual self-determination.

a) The essential ground considered by the legislature as the reason for punishment in § 173 StGB is the protection of marriage and the family. Empirical studies show that the legislature is not acting outside of its latitude for assessment when it assumes that incestuous relationships between siblings can lead to serious consequences damaging the family and society. Incestuous relationships result in overlapping familial relationships and social roles and, thus, can lead to interference in the system that provides structure in a family. This does not correspond with the image of family that is the basis of Article 6.1 GG. It seems conclusive and is not far-fetched that the children of an incestuous relationship have significant difficulties in finding their place in the family structure and in building a trusting relationship to their closest caregivers. The function of the family, which is of primary importance for the human community and which is at the basis of Article 6.1 GG, would be decisively damaged if the required structures were shaken by incestuous relationships.

b) To the extent the criminal provision is justified by reference to the protection of sexual self-determination, this objective is also relevant between siblings. The objection that the protection of sexual self-determination is comprehensively and sufficiently protected by §§ 174 et seq. StGB (crimes against sexual self-determination) and, therefore, does not justify § 173.2 sentence 2 StGB ignores the fact that § 173 StGB addresses specific dependencies arising from the closeness in the family or rooted in family relations as well as difficulties of classification of, and defence against, encroachments.

c) The legislature additionally based its decision on eugenic grounds and assumed that the risk of significant damage to children who are the product of an incestuous relationship cannot be excluded due to the increased possibility of an accumulation of recessive hereditary dispositions. In both medical and anthropological literature, which are supported by empirical studies, reference is made to the particular risk of the occurrence of genetic defects.

d) The challenged criminal provision is justified by the sum of the comprehensible penal objectives against the background of a societal conviction effective to date based upon cultural history regarding the fact that incest should carry criminal penalties, which is also evident in international comparison. As an instrument for protecting sexual self-determination, the public health, and especially the family, the criminal provision fulfils an appellative, law-stabilising function and, thus, a general preventive function, which illustrates the values set by the legislature and, therefore, contributes to their maintenance.

3. The challenged provision is also sufficient in regard to the constitutional-law requirements of suitability, necessity, and proportionality as to a rule that places limitations on freedom.

a) The criminalisation of sibling incest cannot be denied suitability for promoting the desired success. The objection that the challenged criminal provision fails its intended objectives because of fragmentary design and because of the grounds for exemption from penalty in § 173.3 StGB (no punishment for minors) fails to appreciate that through the prohibition on acts of sexual intercourse a central aspect of sexual relations between siblings is penalised which has great significance regarding the incompatibility of sibling incest with the traditional picture of the family, and which finds a further objective justification in the ability, in principle, to cause further damaging consequences by producing descendants. That acts similar to sexual intercourse and sexual intercourse between same-sex siblings are not threatened with criminal penalties, but on the other hand, sexual intercourse between natural siblings also fulfils the elements of the crime even in cases where pregnancy is excluded does not place doubt on the basic achievability of the objectives of protecting sexual self- determination and preventing genetic disease. The same applies to the objection that the criminal provision is unsuitable for protecting the structure of the family because based on the grounds for exemption from punishment as to minors (§ 173.3 StGB) the criminal provision first reaches siblings when they typically are leaving the family circle.

b) The challenged provision also is not subject to constitutional-law doubts in regard to necessity. It is true that in cases of sibling incest guardianship and youth welfare measures come into consideration. However, in comparison to criminal penalties they are not less serious measures with the same effectiveness. Rather, they are aimed at preventing and redressing violations of provisions and their consequences in specific cases; as a rule they do not have any general preventive or law-stabilising effect.

c) Lastly, the threatened punishment is not disproportionate. The range of punishment provided for also allows consideration for suspension of proceedings in accordance with discretionary prosecution aspects, for refraining from punishment, or for special sentencing considerations, in certain case constellations in which the accuseds' guilt is slight so that punishment seems unreasonable.

The dissenting opinion of Judge Hassemer is in essence based on the following considerations:

§ 173.2 sentence 2 StGB is incompatible with the principle of proportionality.

The provision is not aimed at establishing a rule that would be internally consistent and compatible with the elements of the crime. From the outset consideration of eugenic aspects is not an objective of a criminal-law provision that is supportable under constitutional law. Likewise, neither the wording of the provision nor the statutory system indicate that the protective purpose of the provision or even just one such protective purpose could be protection of the right to sexual self-determination. Lastly, the prohibition on sibling incest also is not constitutionally in regard to protection of marriage and the family. Only sexual intercourse between natural siblings is a punishable offence, not, however, all other sexual acts. Sexual relationships between same-sex siblings and between non-blood-related siblings are not encompassed. If the criminal provision were actually aimed at protecting the family from sexual acts, it would also extend to these acts that are likewise damaging to the family. The evidence seems to indicate that the provision in its existing version is solely aimed at attitudes to morality and not at a specific legally protected right. Building up or maintaining societal consensus regarding values, however, cannot be the direct objective of a criminal provision.

In addition, the provision does not offer a suitable path to the objectives pursued through § 173.2 sentence 2 StGB. The elements of the crime, limiting punishability to acts of sexual intercourse between siblings of different gender, is not in a position to guarantee protection of the family from damaging effects of sexual acts. It does not go far enough because it does not encompass similarly damaging behaviour and, moreover, non-blood-related siblings as possible perpetrators. It goes too far because it encompasses behaviour that - based on the children having reached the age of majority and the attendant process of leaving the family - it cannot (any longer) have damaging effects on the family unit.

In addition, there are constitutional-law doubts about criminal liability for sibling incest based on the principle of proportionality in regard to the availability of other official measures that could similarly or even better guarantee the protection of the family, such as youth welfare measures and family court and guardianship measures.

Finally, the criminal provision of § 173.2 sentence 2 StGB conflicts with the constitutional-law prohibition on excessiveness. There is a lack of statutory limitation on criminal liability as to a behaviour that does not endanger any of the possible objects of protection.