It is possible to use an application under CPR 31.17 as an alternative to an application for a Norwich Pharmacal Order.
In Kerner v WX  EWHC 1247 (QB), the Claimant needed to trace the Defendants. She had a registration number and wanted an order requiring the DVLA to disclose the address of the registered keeper of the vehicle with that registration number. The DVLA did not fit within the Norwich Pharmacal jurisdiction because they could not be said to be mixed up in any tort. Warby J allowed an application under CPR 31.17.
s 34 of the Senior Courts Act 1981 provides:
“(2) On the application, in accordance with rules of court, of a party to any proceedings, the High Court shall…have power to order a person who is not a party to the proceedings and who appears to the court to be likely to have in his possession, custody or power any documents which are relevant to an issue arising out of the said claim
(a) to disclose whether those documents are in his possession…; and
(b) to produce such of those documents as are in his possession,…
CPR 31.17 which deals with an order for disclosure against someone who is not a party to the proceedings provides:
(1) This rule applies where an application is made to the court under any Act for disclosure by a person who is not a party to the proceedings.2
(2) The application must be supported by evidence.
(3) The court may make an order under this rule only where—
(a) the documents of which disclosure is sought are likely to support the case of the applicant or adversely affect the case of one of the other parties to the proceedings; and
(b) disclosure is necessary in order to dispose fairly of the claim or to save costs.
In giving Judgment Warby J said
25. The wording of s 34(2) and CPR 31.17(3)(a) is perhaps not plainly and obviously apt to confer a power to order disclosure for the purposes of identifying an unknown party. In my judgment, however, it would be inappropriate to construe either provision in a narrow and literal way…and not as extending to the question of the identity of an unknown party. To take that approach would tend to obstruct or hinder the fair disposal of litigation. I must not forget that the rights, including the Article 8 rights, of those whose identities might be disclosed pursuant to such an order require consideration; the court must conduct a careful balancing exercise…But the statute and the rule confer a discretionary power, which is also subject to the express threshold requirements of CPR 31.17(3)(b) . Those factors mean there is ample scope for deciding, in an appropriate case, that disclosure would represent an unnecessary and disproportionate intrusion into personal privacy, or should not be ordered for some other reason…
26. I am satisfied that the question of the identity of the unknown defendant who was the driver of the [vehicle] …is aptly described as an “issue arising out of the claim” in this action. I would regard documents held by the DVLA which identify the registered keeper as “relevant to” that issue, as there is a good chance that they would identify or lead to the identification of the person who was the driver on the relevant occasion. Are the documents such as might “support the case” of the claimant, within the meaning of r. 31.17(3)(a) ? I would interpret that phrase as encompassing documents that would advance the case of the claimant by identifying the defendant and answer the question yes.
27. I am also satisfied that it is “likely” that the documents would assist the claimant in that way. The word “likely” in this context means “may well” rather than “probably will”:..In my judgment the requirement of necessity in CPR 31.17(b) is also met, as the claim cannot be disposed of fairly without identification of the defendants. Moreover, it is likely in my judgment that once one or both have been identified the action will be resolved more swiftly and economically than might otherwise be the case. I have no hesitation in exercising my discretion in favour of the order sought.