21Powers of chairman to require production of evidence etcU.K.
(1)The chairman of an inquiry may by notice require a person to attend at a time and place stated in the notice—
(a)to give evidence;
(b)to produce any documents in his custody or under his control that relate to a matter in question at the inquiry;
(c)to produce any other thing in his custody or under his control for inspection, examination or testing by or on behalf of the inquiry panel.
(2)The chairman may by notice require a person, within such period as appears to the inquiry panel to be reasonable—
(a)to provide evidence to the inquiry panel in the form of a written statement;
(b)to provide any documents in his custody or under his control that relate to a matter in question at the inquiry;
(c)to produce any other thing in his custody or under his control for inspection, examination or testing by or on behalf of the inquiry panel.
(3)A notice under subsection (1) or (2) must—
(a)explain the possible consequences of not complying with the notice;
(b)indicate what the recipient of the notice should do if he wishes to make a claim within subsection (4).
(4)A claim by a person that—
(a)he is unable to comply with a notice under this section, or
(b)it is not reasonable in all the circumstances to require him to comply with such a notice,
is to be determined by the chairman of the inquiry, who may revoke or vary the notice on that ground.
(5)In deciding whether to revoke or vary a notice on the ground mentioned in subsection (4)(b), the chairman must consider the public interest in the information in question being obtained by the inquiry, having regard to the likely importance of the information.
(6)For the purposes of this section a thing is under a person's control if it is in his possession or if he has a right to possession of it.