The facts behind the case are notorious; the law elucidated is notable. See the background legal discussion on the history of citizenship laws, the process behind deprivation, the relevance of the best interests of affected children and the relevance (or rather lack of it) of EU law at paragraphs 26 to and the official headnote:
(i) While the two fold duties enshrined in section 55 of the Borders, Citizenship and Immigration Act 2009 are imposed on the Secretary of State, the onus of making representations and providing relevant evidence relating to a child’s best interests rests on the appropriate parental figure.
(ii) A failure to discharge this onus may well defeat any argument that there was a proactive duty of enquiry on the Secretary of State in a given context.
(iii) In deprivation of citizenship cases, section 55 issues arise at two stages: at the deprivation of citizen stage and at the later stage of proposed removal or deportation.
(iv) As the subject of national citizenship lies exclusively within the competence of Member States, EU law has no role to play in deprivation cases: G1 v SSHD  EWCA Civ 867 applied.
(v) The Secretary of State’s deprivation of citizenship policy confers a wide margin of appreciation on the decision maker.
(vi) Part 5A of the Nationality, Immigration and Asylum Act 2002 does not apply to deprivation of citizenship decisions as such decisions are not made under the Immigration Acts.
(vii) There would be a considerable saving of human and financial resources with consequential reduced delay if deprivation of citizenship and deportation or removal decisions were to be made jointly.
Source: Ahmed and Others (deprivation of citizenship)  UKUT 00118 (IAC)