notice of the inquiry may be given and published in accordance with Such general or special directions as the Secretary of State may give;

the Secretary of State and, if authorised by him, the person appointed to hold the inquiry, may by order require any person, subject to the payment or tender of the reasonable expenses of his attendance, to attend as a witness and give evidence or to produce any documents in his possession or power which relate to any matter in question at the inquiry, and are such as would be subject to production in a court of law;

the person holding the inquiry shall have power to take evidence on oath and for that purpose to administer oaths;

the Secretary of State may make such order as to the payment of the costs incurred by him in connection with the inquiry (including such reasonable sum not exceeding £30 a day as he may determine for the services of any officer engaged in the inquiry) by such party to the inquiry as he thinks fit, and may certify the amount of the costs so incurred, and any amount so certified and directed by the Secretary of State to be paid by any person shall be recoverable from that person, and shall be so recoverable, in England or Wales, either as a debt to the Crown or by the Secretary of State summarily as a civil debt, and in Scotland by the Secretary of State.