This appeal arises from the detention and mistreatment of 12 individuals in August 1971, following a major arrest operation in Northern Ireland, carried out using powers of detention referred to as "internment." The group of individuals has come to be known as the "hooded men." The men were detained in the custody of the Royal Ulster Constabulary, with support provided by military personnel. During their detention, Francis McGuigan and Mary McKenna’s father (Sean McKenna) were subjected to treatment which was later found by the European Court of Human Right to have been in breach of article 3 of the European Convention on Human Rights.
                The judicial review proceedings leading to this appeal were issued following the discovery, via a 2014 RTE Documentary, of additional documentary materials relevant to the mistreatment in question. Following such discovery, the Chief Constable of the Police Service of Northern Ireland stated that he would arrange a further investigation into the mistreatment. The present proceedings raise a number of issues concerning the compatibility of the proposed investigation with the European Convention on Human Rights and with the common law.

On the night of 8 June 1972, Jean Smyth was a passenger in a car which was stationary on the Glen Road, Belfast, when she was fatally wounded by a bullet striking her head. Following police investigation into her death and following the discovery of military logs suggesting the possibility that the fatal shot was fired by a member of the Military Reaction Force, the Police Service of Northern Ireland proposed to conduct a further investigation into Ms Smyth’s death. The investigation was to be conducted by the Police Service’s Legacy Investigations Branch. Before the proposed further investigation took place, the respondent issued judicial review proceedings seeking a declaration that the proposed further investigation of the death conflicted with the requirements of article 2 ECHR on the basis that the lacked the requisite independence required to perform an Article 2 compliant investigation into the death.
                The Court of Appeal found, in the appellant’s favour, that article 2 was applicable and that the Police Service lacked the requisite independence to satisfy the requirements under article 2. The appellants appeal to this court against the Court of Appeal’s findings. The respondent cross-appeals.