In the wake of the leaking of Murray McCully's emails, several people have speculated as to why McCully was having his emails forwarded to an insecure xtra account. Was it an attempt to avoid the Official Information Act? While McCully may very well have believed that, if he did, he'd be mistaken. Because there is no legal way of avoiding the OIA.
The interpretation section of the Act is pretty clear: if its held by a Minister in their official capacity, then its official information and covered by the Act. This is regardless of format and regardless of location. The Ombudsman's Practice Guidelines [PDF] take a very broad view on this. For example:
The Ombudsmen consider that the definition of official information also includes knowledge of a particular fact or state of affairs held by officers in such organisations or departments in their official capacity. The fact that such information has not yet been reduced to writing does not mean that it does not exist and is not “held” for the purposes of the Act.That's right: information in Minister's heads is official information, and they can be forced to write it down for you. Given this, official emails stashed in a "private" xtra account are certainly covered.
Of course, private accounts give you deniability, in that you can pretend that the documents therein don't exist. But that only works as long as no-one knows about them. And following this, I expect that Ministers are already being inundated with a flood of OIA requests asking whether they ever send or receive official emails on other accounts, and if so, why, how often and what are the addresses of those accounts. Of course, the Minister could lie, but if you can show that - and I think its the moral duty of the public servants doing the forwarding to do so - then its head on a spike time. Sadly, consciously attempting to evade the OIA doesn't carry a penalty of jail-time sufficient to disqualify a Minister from sitting in Parliament - but it damn well should.