Article 6 requires a tribunal falling within its scope to be impartial. Impartiality normally denotes absence of prejudice or bias and its existence or otherwise can be tested in various ways. The Court has thus distinguished between a subjective approach, that is endeavouring to ascertain the personal conviction or interest of a given judge in a particular case, and an objective approach, that is determining whether he or she offered sufficient guarantees to exclude any legitimate doubt in this respect.
In applying the subjective test the Court has consistently held that the personal impartiality of a judge must be presumed until there is proof to the contrary. The principle that a tribunal shall be presumed to be free of personal prejudice or partiality is long established in the case-law of the Court.
As to the second test, when applied to a body sitting as a bench, it means determining whether, quite apart from the personal conduct of any of the members of that body, there are ascertainable facts which may raise doubts as to its impartiality. In this respect, even appearances may be of some importance. When it is being decided whether in a given case there is a legitimate reason to fear that a particular body lacks impartiality, the standpoint of those claiming that it is not impartial is important but not decisive. What is decisive is whether the fear can be held to be objectively justified.
Driza v Albania  ECHR 919. (Three of the Albanian Supreme Court's judges sat in the decision-making body which ruled on his case and were also part of the decision-making body which delivered the judgment: both ruled against him.)
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