The principle in the decision of the House of Lords is that the role of the special advocates is consistent with U.K. and European law. The one caveat was that the House of Lords added that it might be in exceptional circumstances that special advocates will not be sufficient to ensure a fair process. In these exceptional cases the trial judge should have discretion to find that the role of the special advocate is not sufficient and to not allow the government to proceed based on the secret information. That is for exceptional circumstances. The norm is that special advocates are sufficient to ensure a fair process.
On November 27th, 2007. See this statement in context.