Williams was appealing the four-match ban from the Lions series that rules him out of the first Bledisloe Cup clash against the Wallabies.
The All Blacks centre was handed the suspension for his second Test send-off against the British & Irish Lions earlier this month.
Williams became the first All Black in 50 years to be sent off in a Test when he was red-carded for a shoulder charge on Lions winger Anthony Watson early in the 24-21 loss in Wellington.
He missed the drawn third Test with the Lions, and the Blues' final Super Rugby match against the Sunwolves.
Two pre-season Counties-Manukau matches, one against North Harbour and one an inter-squad match, were presented by NZ Rugby to the World Rugby Judicial Committee as completing the four-match ban.
But the disciplinary committee ruled the inter-squad match did not meet the grade as a meaningful match.
The appeal was heard last night via video conference before a committee chaired by Mr Justice Graeme Mew (Canada) along with Shao- Ing Wang (Singapore) and Stefan Terblanche (South Africa).
After a two hour hearing the committee reserved their decision, committing to delivering its decision as soon as practicable given the circumstances.