Both players appeared before a Sanzar judicial hearing in Wellington yesterday and judicial officer Nick Davidson QC issued his findings today after reserving his judgement.
He found Rhodes was guilty of a dangerous tackle ruling he had flipped Piutau over in a dangerous manner "placing his head and neck at serious risk of injury".
Davidson added that video evidence showed Piutau in a highly compromised and dangerous position.
Rhodes' six-match ban rules him out of all rugby until July 31.
Davidson cited "exceptional circumstances" over his decision not to punish Piutau for punching despite the winger admitting foul play.
He said Piutau's reaction was that of someone who had been "seriously endangered".
He added that to impose a sanction in these circumstances "would not reflect the effect on Piutau of the incident and a reaction that was the product of shock rather than retaliatory intent".
The citings related to an incident in the 59th minute of the match, won 26-22 by the Lions, in which Rhodes used a headlock to clear Piutau from a ruck.
Piutau retaliated by twice punching Rhodes in the head.
