Graham McCready has launched four private prosecutions against Peter Dunne:
Three were allegations of breaches against the Crimes Act, linked to allegations Dunne leaked a copy of a report into the Government Communications Security Bureau (GCSB).
The fourth alleged fraud, linked to Dunne being awarded parliamentary funding as the leader of a political party, when UnitedFuture had insufficient numbers to declare that the party had 500 members.
Unlike his other cases against Trevor Mallard and John Banks, I think there's not a hope in hell of any of these going anywhere. On the fraud charge, the Bill of Rights 1688 bars the courts from inquiring into Parliamentary business (and whether a disclosure is made to the Speaker / whether a party should be recognised by the Speaker is very much the business of Parliament). On the former cases, Stuff is sadly nonspecific about the exact charges, but they're likely to be either espionage or some variations of wrongful communication, retention, or copying of official information. The first thing to note is that all of these offences require that the information disclosed be "likely to prejudice the security or defence of New Zealand". That's a joke, and John Key has said as such. The second point is that they all require the consent of the Attorney-General, which given the first point is unlikely to be forthcoming. The third point is that one of the limbs of wrongful communication specifically refers to official information, defined in the same terms as used in the Official Information Act (that is, held by certain specified bodies). But if the allegation is that Dunne leaked official information held by the Intelligence and Security Committee, then that cannot be true, because the ISC is not subject to the OIA and so its information is not "official information". Similarly he cannot have leaked material held by a Minister (in this case himself) in an official capacity because he did not hold the Kitteridge report in such a capacity (it was given to him as a government coalition partner, not as a Minister).
What about the other limbs? They require the intent to prejudice the security and defence of New Zealand - see point one above - or that Dunne had been ordered to return the report before he leaked it (which there's been no suggestion of). Basically its difficult to see any case whatsoever. And I think if there was, the police would have stepped in already.