Interrogatories
Overview
A party may formally ask the other party to answer questions to assist in litigation. It may be used to obtain admissions.
The purpose of interrogatories is to avoid injustice to one party who lacks the knowledge and the ability conveniently to prove facts which are important to be established in aid of the party, where such party does not have the knowledge or ability to prove the facts either at all or without undue difficulty.
Interrogatories may be sought without leave in the commercial list and competition list and in cases involving fraud and breach of trust.
The courts encourage the use of interrogatories because they can narrow the issues which are in dispute and need to be proved. However, Â their use is relatively unusual
Where Permitted
In any case matter where relief is sought by way of damages or otherwise sought on the ground of fraud or breach of trust the plaintiff may at any time after delivering his statement of claim or after delivery of his defence deliver one set of interrogatories to the other side without an order having been first obtained. Fraud in this context means criminal fraud but also equitable fraud on the part of a fiduciary or trustee.
In other cases (other than fraud breach of trust commercial list or competition last interrogatories may not be delivered without the leave of the court. This may be sought after pleadings have closed and if appropriate particulars have been raised and responded to, and any necessary discovery agreed or obtained by order.
Delivery of interrogatories is permitted without leave in all cases in the Commercial List and the Competition List.
In any matter where relief is claimed by way of damages or otherwise is sought on the ground of fraud or breach of trust, the claimant may, after delivering his statement of claim and the defendant may at any time after delivering his defence, without an order, and in every other case may with an order upon such terms as the security for costs or otherwise, as the Court may direct, deliver interrogatories in writing for examination of the opposite party or one or more of them.
Such interrogatories when delivered shall have a note stating which of the interrogatories each person is to answer. No party shall deliver more than one set of interrogatories to the same party without an order for that purpose. Interrogatories which do not relate to any matters in question in the cause or matter shall be deemed irrelevant, notwithstanding that they may be admissible on oral cross-examination.
Application
A copy of interrogatories proposed to be delivered is to be delivered with the notice of application for leave to deliver them, unless the Court otherwise orders. The interrogatories sought to be delivered shall be submitted to and considered by the Court.
In deciding on the application, the Court shall take into account any offer which may be made by the party sought to be interrogated, deliver particulars or make admissions or to produce documents relating to the matter in question. Leave should be given as to such only of the interrogatories as should be necessary either for disposing fairly of the cause or matter or for saving costs.
If interrogatories have been issued exhibited, unreasonably, vexatiously or of  improper length, the costs occasioned by them may be required to be paid on taxation by the party at fault.
Interrogatories are in a prescribed form. In the case of companies, interrogatories may be delivered to any member or officer of such corporation for response.
Criteria for Leave
The party seeking to serve interrogatories must demonstrate the saving to be achieved. The court may assess whether more is likely to be gained by full discovery over that which might be achieved by other measures such as interrogatories. It balances that consideration against what might be saved in terms of resources by adopting other means.
The application for leave is grounded on affidavit and is made to the Master of the High Court. A copy of the proposed interrogatories is to be exhibited. The court considers
- whether the information sought is relevant to the matters in issue in the proceedings
- whether interrogatories are necessary for disposing fairly of the matter or saving costs
- that the interrogatories are not vexatious or oppressive or unfair to the party addressed
The court is to take account of any offer which may be made by the party to be interrogated to deliver particulars, make admissions or to produce documents relating to any matter in question.
When leave is granted, time is given within which interrogatories must be answered. The person to answer should be identified. This will be the party or officer of a company.
It is possible in principle for interrogatories  to be served on a non-party. This requires leave of the court. Similar provisions as apply to third  party discovery are applicable.
Objection & Set Aside
Any objection to answering interrogatories on the ground that they are scandalous, irrelevant, not bona fide for the purpose of the cause or the matters inquired into, Â not sufficiently material at that stage or on other ground, may be taken in the affidavit in answer.
Interrogatories may be set aside on the ground that they are have been issued unreasonably, vexatiously or on the ground that they are prolix, oppressive, unnecessary, or scandalous. An application for this purpose may be made within seven days after service.  The party addressed may raise objections in their affidavit in the alternative.
Format
Interrogatories are usually in the form of a leading question seeking a yes or no answer. Consistent with the encouragement of interrogatories, the courts have indicated that the use of interrogatories is to be encouraged and somewhat expanded because their usefulness does not come with significant logistical and cost considerations that often attaches to the discovery process.
The interrogatory procedure potentially applies to facts which can be admitted by way of a simple statement which does not require narrative or opinion. The party addressed is required to answer interrogatories upon affidavit.
Valid Questions
It is possible to make objections to interrogatories on  much the same grounds as objections to questions in cross examination. The court may amend or rephrase interrogatories as it considers necessary.
Interrogatories may seek information in relation to the facts in dispute. This extends to facts the existence or otherwise of which tend to prove a fact in dispute. The facts must be reasonably relevant to establish facts in issue.
They cannot seek information as to evidence. Sometimes the distinction between facts and evidence to establish facts may not be clear. A distinction may more easily be drawn between questions that seek to elicit facts and those which seek to elicit more complex matters such as opinions inferences and intentions. The latter would not be permitted. They are more appropriate for examination and cross-examination.
Answer to Interrogatories
Interrogatories shall be answered by affidavit to be filed within ten days or such other period,  as the Court allow. Answers to interrogatories are to be in a prescribed form.
No exception shall be taken to any affidavit in answer. The sufficiency or otherwise of any such affidavit objected to as insufficient shall be determined by the Court on motion.
If any person interrogated omits to answer or answers insufficiently, the party interrogating may apply to Court for an order requiring him to answer or to answer further, as the case may be. The order may require him to answer by affidavit or verbally by examination.
Interrogatories must be answered on affidavit. The person concerned must answer from his knowledge of the position as he believes to be true. The person answering interrogatories appears to be obliged to make reasonable enquiries to satisfy himself as to the accuracy of the answers given. This may involve making enquiries.
An objection to answering interrogatories may be set out in the affidavit on the basis that the matter or questions are scandalous, irrelevant not bona fide for the purpose of the matter in question or are not material to it.
Where the person served with interrogatories fails to answer interrogatories at all or sufficiently, the  party interrogating may apply to court for an order requiring him to answer. It is made on  affidavit. This must be done within a reasonable time of the answer given.