White was cited by the match citing commissioner, Richard McGhee from Scotland, for allegedly stamping on Saracens centre Brad Barritt during the first half of the Pool 3 game at Allianz Park in contravention of law 10.4(b).
Law 10.4(b) - A player must not stamp or trample on an opponent.
Under the IRB Sanctions for Foul Play, law 10.4(b) carries the following sanction entry points - low end: two weeks; mid-range: five weeks, and top end: nine to 52 weeks.
The independent judicial officer, Roger Morris from Wales, heard evidence and submissions from White, who pleaded guilty to the offence, from the Connacht Rugby legal representative, Kevin Dineen, and from the ERC disciplinary officer Roger O'Connor.
In upholding the citing complaint, the judicial officer determined that the offence was in the mid-range (five weeks) of the IRB sanctions for offences of this nature.
As there were no aggravating factors, he reduced the suspension by two weeks due to the player's guilty plea, his clean record, good conduct, and his remorse during the hearing.
The three-week suspension will run over a five-week term as the judicial officer chose to take into account two weeks during the period when the player would not have played.
Both the player and ERC have the right to appeal the decision.
Meanwhile, the citing complaint against Connacht scrum half Kieran Marmion, arising from the Saracens game, was upheld following an independent disciplinary hearing.
It was also decided that the act of foul play committed by the player did not warrant a red card, and Marmion is therefore free to play. He is on the bench for the O2 Ireland Wolfhounds' clash with England Saxons in Gloucester on Saturday.
Marmion was cited by citing commissioner McGhee for striking Saracens replacement scrum half Neil de Kock during the second half of the Pool 3 tie in contravention of law 10.4(a).
Law 10.4(a) - Punching or striking - a player must not strike an opponent with the fist or arm, including the elbow, shoulder, head or knee(s).
Under the IRB Sanctions for Foul Play, law 10.4(a) - striking a player with the head - carries the following sanction entry points - low end: four weeks; mid-range: ten weeks, and top end: sixteen-plus to 104 weeks.
Independent judicial officer Morris analysed both video footage of the incident and written submissions from Connacht team manager Tim Allnutt, Neil de Kock and ERC disciplinary officer O'Connor.
The judicial officer upheld the citing complaint, in that Marmion committed an act of foul play, however, he decided that it did not warrant a red card and that no sanction should be imposed.