Is it possible to ask for too much information?

Technically, no – you can request as much information as you like.  Practically speaking, however, there is the possibility that if you request too much information, the public authority might refuse to provide it relying on the provisions of s19 of the Act.

Section 19 allows a public authority or Minister to refuse your application if the work involved in providing the information requested –

• would substantially and unreasonably divert the resources of the public authority from its other work; or
• would interfere substantially and unreasonably with the performance by that Minister of the Minister's other functions.

If a public authority or Minister is considering a refusal under s19, you must be given a reasonable opportunity to consult the public authority or Minister with a view to being helped to make an application in a form that would remove the ground for refusal.

This is designed to give you a practical and reasonable opportunity to understand why dealing with your request may be a substantial and unreasonable diversion of resources and to negotiate with the authority or Minister.  It is then up to you whether you think your request is still a reasonable one and you wish to persist with it, or whether you are prepared to revise your application to reduce the work required to process it and remove the grounds for refusal.