Reports claiming former ACC chairman John Judge hampered an ACC investigation has led to a surge in trading on iPredict on whether Judge himself leaked sensitive emails to the media.

ACC Minister Judith Collins has commented about an investigation into who leaked an email which identified Bronwyn Pullar as the woman at the centre of a massive ACC privacy breach. She said the investigation was stymied by Judge after he replaced one computer and wiped data from his iPad.

Although Judge dismissed the claims as an attempt to blacken his name, trading on prediction website iPredict on whether Judge was involved in the leak has surged to 10 times its normal volume.

According to betting on the site by mid-afternoon, traders believed there was a 43 per cent chance Judge was involved in the leaking of the email, with the probability having risen as high as 90 per cent earlier in the day.

Yesterday Judge was seen as a 12 per cent chance of being involved in the emails leaking.

The odds that a more junior ACC staffer leaked the email dropped 9 per cent to 33 per cent today, while the odds a Beehive staffer leaked the email dropped 22 per cent to 5 per cent.

The odds of Bronwyn Pullar herself being involved in the leak dropped to 3 per cent.

Trevor Mallard, who is being sued for defamation by Collins, said today he "accepts John Judge's word" and that "people who are interested in iPredict should sell short on that contract" as the price will fall quickly again.

- © Fairfax NZ News