When the matter was before the European Court of Human Rights' Grand Chamber, the non-governmental organizations Liberty and Privacy International were granted permission to file third-party submissions and submitted scientific evidence on the private nature of genetic material and information contained in DNA samples.
Liberty stressed that general principles of European human rights law dictated that interference by a member state with an individual's rights under the Convention must be “necessary in a democratic society” and have a legitimate aim to answer a “pressing social need"; even then an identified interference must be proportionate and remains subject to review by the Court (Coster v United Kingdom (2001) 33 EHRR 479)).
The applicants stressed that the nature of DNA samples, which included a myriad highly personal data pertaining to an individual's unique identity, susceptibility to certain medical conditions and was linked to genetic information of their relatives, meant that not only the taking of the data, but its storage, retention and constant automatic corroboration against other samples taken from current criminal investigations, caused them to suffer unwanted stigma and adverse psychological consequences.
In response, the United Kingdom submitted that the use of the DNA samples was permitted under the Police and Criminal Evidence Act 1984 and did not fall under the scope of Article 8 of the Convention.
The DNA profile was merely a sequence of numbers which provided a means of identifying a person against bodily tissue and was not materially intrusive; the retention of data was a legitimate aim because it assisted in the identification of future offenders.
The Court did therefore not go on to consider whether the retention of DNA was also a breach of Article 14 (prohibition of discrimination) as the applicants had also argued that they had suffered detrimental treatment on the basis of an acquired status.
Notably, another part of the United Kingdom, namely Scotland, had provided an example of a proportionate, more rational approach in regard to DNA retention, in that samples were to be destroyed if an individual was not convicted or was granted an absolute discharge; an exemption however exists for the authorities to retain samples if the individual is suspected of certain sexual or violent offences (Retention Guidelines for Nominal Records on the Police National Computer 2006).
Through this ruling, the European Court of Human Rights has further developed its body of jurisprudence on what measures are likely to fall outside a state's margin of appreciation.
This decision has been criticised, particularly since it was open to the court to declare the blanket DNA retention policy incompatible with the European Convention of Human Rights.