Rimes performed an awkward duet with 13-year-old contestant Carly Rose Sonenclar on Wednesday (December 19), prompting speculation that she was inebriated during the show.
The 30-year-old singer came out to defend herself after the show, denying that she was drunk and condemning the "gossip and lies" surrounding the performance.
Cowell, who serves as executive producer and judge on the reality series, has now called Rimes's performance "interesting", reports TMZ.
When asked if he thought the singer was inebriated, he smirked: "No, I think she was just happy... LeAnn's welcome any time."
Sonenclar's family were allegedly angry with Rimes over the performance.
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