He was reported for breaching CA's code of conduct in making a comment detrimental to the interests of cricket while playing for Melbourne Stars against the Perth Scorchers in a BBL semi-final in Perth on January 24.
The offence occurred during the Scorchers' innings, when batsman Sam Whiteman was given not out following an appeal for caught behind by the Stars, and Pietersen commented on the umpire's decision while wearing a microphone on-field.
Under the code procedure, match referee David Talalla considered the umpires' report and the proposed sanction was a Aus$5,000 ($3,800) fine.
Pietersen accepted the charge but elected to dispute the sanction. The match referee set a hearing for Thursday and announced the decision was upheld Friday.
Pietersen now has 48 hours to decide whether to appeal and have the matter heard by a CA code of conduct commissioner.
First Published: February 3, 2017, 12:07 PM IST