Supreme Court Rules 2000

If –

there is reasonable cause to believe that the applicant has or may have the right to obtain relief in the Court from a person whose description has been ascertained; and after making all reasonable inquiries, the applicant does not have sufficient information to enable a decision to be made as to whether or not to commence a proceeding in the Court to obtain that relief; and there is reasonable cause to believe that – that person has or is likely to have, or has had or is likely to have had, in that person's possession any document relating to the question whether the applicant has the right to obtain the relief; and inspection of the document by the applicant would assist in making the decision –

the Court or a judge may order that person to make discovery to the applicant of any document of the kind described in paragraph (c).