The mum-of-five, who was married to the singer until 2009, believes the High Court judge’s words may help her own legal battle against him in January.
Katie is seeking damages from her former manager Claire Powell, who still manages her ex-hubby Pete, alleging that they misused private information about her.
A source told Closer magazine: “Katie can’t hide her glee over the judge’s comments. She had told friends that for so long she’s been painted as a villain and Pete’s been seen as this golden boy.
“She feels Pete being branded a liar works in her favour in their court case. She says to finally win after three years would be the ultimate revenge on him. She feels Pete has dragged her name through the mud and she wants justice.”