"A person seeking to enter the United Kingdom and claiming to have the right of abode there shall prove that he has that right by means of either – (a) a United Kingdom passport describing him as a British citizen or as a citizen of the United Kingdom and Colonies having the right of abode in the United Kingdom; or (b) a certificate of entitlement issued by or on behalf of the Government of the United Kingdom certifying that he has such a right of abode."
"(1) Subject to the provisions of this Part of this Act , a person who is refused leave to enter the United Kingdom under this Act may appeal to an adjudicator against the decision that he requires leave or against the refusal.
"Where the respondent to an appeal alleges that - (a) the appellant is not entitled to appeal
“Where the respondent to an appeal makes such an allegation as is mentioned in Rule 8(3), the appellant authority may, and at the request of the respondent shall, determine the validity of the allegation as a preliminary issue."
"(c) any function conferred on the Tribunal to (i) determine a preliminary issue, or to make a determination in consequence thereof, pursuant to Rule 11 above;
"Any irregularity resulting from failure to comply with these Rules before an appellate authority has reached its decision shall not by itself render the proceedings void, but the appellate authority may, and shall if it considers that any person may have been prejudiced, take such steps as it thinks fit before reaching its decision to cure the irregularity, whether by amendment of any document, the giving of any notice or otherwise."
"Even when such powers are not conferred, it is possible that statutory tribunals would have power, as has the High Court, to correct accidental mistakes; to set aside judgments obtained by fraud; and to review a decision where facts subsequently discovered have revealed a miscarriage of justice."