The EU is itself on a road toward becoming a signatory to the convention - Council of Europe. It is argued by the Council of Europe that the EU's accession will strengthen the protection of human rights in Europe, by submitting the EU’s legal system to independent external control. It will also close gaps in legal protection by giving European citizens the same protection vis-à-vis acts of the EU as they presently enjoy from member states. The Court of Justice of the EU (CJEU) has also recognised and applied human rights when making decisions in particular cases - see, for example, the article by Elizabeth F. Defeis "Human Rights and the European Court of Justice" (2007) 31 Fordham International Law 5.
important international agreement is the Charter of Fundamental Rights of the EU (the charter). The Charter brings together in a single document the fundamental rights protected in the EU. The Charter contains rights and freedoms under six titles: Dignity, Freedoms, Equality, Solidarity, Citizens' Rights, and Justice. Proclaimed in 2000, it was hoped by the EU that the Charter would become legally binding on all EU member states with the entry into force of the Treaty of Lisbon, on 1st December 2009. However, the United Kingdom entered into a Protocol to the Lisbon Treaty which has been, misleadingly, often referred to as an 'opt out' to the Charter.
The 'opt out' (so called):
A Protocol to the Lisbon Treaty states:
1. The Charter does not extend the ability of the Court of Justice of the European Union, or any court or tribunal of Poland or of the United Kingdom, to find that the laws, regulations or administrative provisions, practices or action of Poland or of the United Kingdom are inconsistent with the fundamental rights, freedoms and principles that it reaffirms.
2. In particular, and for the avoidance of doubt, nothing in Title IV of the Charter creates justiciable rights applicable to Poland or the United Kingdom except in so far as Poland or the United Kingdom has provided for such rights in its national law.
To the extent that a provision of the Charter refers to national laws and practices, it shall only apply to Poland or the United Kingdom to the extent that the rights or principles that it contains are recognised in the law or practices of Poland or of the United Kingdom
Title IV (Solidarity) is concerned with workers rights.
The Lisbon Treaty and the protocol have effect in English law because of the European Communities Act 1972 s.2 and the European Union (Amendment) Act 2008. (UK Parliament approves EU Treaty).
I have always found the drafting of the protocol to be inelegant and its effect to be unclear. It may well be thought that the cumbersome wording was designed to deny to the British people the rights etc. conferred by the charter except to the extent that the British government chose to permit such rights in national law by procuring the enactment of legislation by the UK Parliament. In other words: an "opt out."
However, in Case C-411/10 and C-493/10, R (NS) v Secretary of State for the Home Department  QB 102 the Court of Justice of the EU took a different view and decided that article 1(1) of the protocol explains article 51 of the Charter with regard to the scope thereof and does not intend to exempt the Republic of Poland or the United Kingdom from the obligation to comply with the provisions of the Charter or to prevent a court of one of those member states from ensuring compliance with those provisions. This case was a reference to the CJEU from the Court of Appeal (Civil Division) - see R(NS) v Secretary of State for the Home Department  EWCA Civ 990.
Article 51 states: Field of application
1. The provisions of this Charter are addressed to the institutions, bodies, offices and agencies of
the Union with due regard for the principle of subsidiarity and to the Member States only when they are implementing Union law. They shall therefore respect the rights, observe the principles and promote the application thereof in accordance with their respective powers and respecting the limits of the powers of the Union as conferred on it in the Treaties.
2. The Charter does not extend the field of application of Union law beyond the powers of the
Union or establish any new power or task for the Union, or modify powers and tasks as defined in the Treaties
As explained by Mark Elliott on the Public Law for Everyone blog, the "opt out" is not really an opt-out at all: it merely clarifies the provision already made by the Charter itself concerning its scope of application.
See also Who's right about the EU Charter of Fundamental Rights? - Head of Legal blog 22nd November - for a detailed analysis of the position by Carl Gardner. (This link added 22nd November).
Judgment of Mostyn J:
Entering into the fray came Mostyn J in R (AB) v Secretary of State for the Home Department  EWHC 3453 (Admin). The learned judge said at paras 12 and 13:
'Although the language of this protocol reveals a certain amount of political haggling, to my mind it is absolutely clear that the contracting parties agreed that the Charter did not create one single further justiciable right in our domestic courts ......
However, my view that the effect of the seventh protocol is to prevent any new justiciable rights from being created is not one shared by the Court of Justice of the European Union (CJEU) in Luxembourg .....'
and then at para 14, Mostyn J said:
'The constitutional significance of this decision can hardly be overstated. The Human Rights Act 1998 incorporated into our domestic law large parts, but by no means all, of the European Convention on Human Rights. Some parts were deliberately missed out by Parliament. The Charter of Fundamental Rights of the European Union contains, I believe, all of those missing parts and a great deal more. Notwithstanding the endeavours of our political representatives at Lisbon it would seem that the much wider Charter of Rights is now part of our domestic law. Moreover, that much wider Charter of Rights would remain part of our domestic law even if the Human Rights Act were repealed.' (My emphasis).
The cat among the pigeons:
As might be expected, Mostyn J's judgment has put the cat among the pigeons in the Ministry of Justice and in other political circles. Perhaps more accurately, it might be said that it is the Court of Justice of the EU which threw the cat in. However that may be, the Secretary of State for Justice has indicated that the government will seek a suitable case to challenge this view - see The Guardian 19th November 2013.
Denying to the British people rights enjoyed by nationals of other EU member states is a political question and it must be remembered that it is not just the Conservative Secretary of State who is doing this. It was a Labour government which signed the Lisbon Treaty - (Gordon Brown arrived late) - and entered into the Protocol which, according to the CJEU, is not an "opt out" after all and, indeed, may never have been more than just a rather confusing clarification of the application of Article 51.
The view expressed by the British government in its submission to the Court of Appeal in R(NS) v Secretary of State for the Home Department was (para 7):
" ..... the Secretary of State accepts, in principle, that fundamental rights set out in the Charter can be relied on as against the United Kingdom, and submits that the Judge erred in holding otherwise (judgment, paragraphs 155 and 157, first sentence). The purpose of the Charter Protocol is not to prevent the Charter from applying to the United Kingdom, but to explain its effect."
In so far as the Charter has any effect in English law it will, in any event, be limited to cases where EU law is under consideration. This follows from Art 51.1 (quoted above) which contains the phrase 'only when they are implementing Union law.'
Interesting material on this topic appears at UK Human Rights blog (The EU Charter: are we in or out) where, back in 2011, Rosalind English considered the effect of the so-called opt out. Rosalind English has also contributed a further article on 8th November 2013.
Open Europe Blog - New light shed on Tony Blair's Charter of Fundamental rights "opt out" - 5th March 2013
The role of EU law in the human rights sphere is now the subject of one of the UK government’s “balance of competences” reviews, which contains a detailed and helpful explanation of the relationship between EU law, the ECHR and domestic law in the human rights field.
Who's right about the EU Charter of Fundamental Rights? - Head of Legal blog 22nd November - a detailed analysis of the position by Carl Gardner.
Today Chris Grayling told parliament the law is unclear. In 2010, Theresa May said it was clear. 😣 pic.twitter.com/bUIus4ddHz ht @AdamWagner1
— Jon Mack (@JonDMack) November 19, 2013