A Sanzaar spokesman told the Herald the judiciary "was adjourned last night seeking further evidence".
According to the spokesman, the governing body "will issue further news when we have it".
The All Blacks have two tests remaining before they face South Africa in the World Cup opener in Yokohama on September 21.
England coach Eddie Jones, meanwhile, has labelled Barrett's red card as "ridiculous", and called on World Rugby to be consistent after he claimed two Welsh players escaped red cards following similar offences against England on the weekend.
According to UK reports, there were two similar tackles in England's win over Wales at Twickenham with both Wales halfback Aled Davies and No 8 Ross Moriarty escaping a red card or a yellow card for incidents on George Ford and Piers Francis respectively.