"I would love to sit in that chair and, you know, give some advice from the contestant's standpoint because I've been on that stage and I know what it's like," Locke said Monday in an interview with The Associated Press.
But don't consider her a pushover. Locke says she'll be brutally honest about each performance and "give it with no fluff."
"When you're a contestant on that show you do need that hard truth sometimes," Locke says, anticipating her critical tone would fall somewhere between the styles of two former judges.
"I'm not quite as nice as Paula (Abdul). Paula's super, super nice but I don't think I'm quite as mean as Simon (Cowell) either."
The empty judges' chairs came after Steven Tyler and Jennifer Lopez decided not to come back for another season. Last week, Mariah Carey confirmed she would join the show's 12th season. Other names mentioned to fill the missing spot include Nick Jonas, Pharrell Williams and Charlie Sheen.
Regardless of if Locke were to get the call, she loves the idea of former contestants coming back to judge. Adam Lambert has also been vocal about his willingness to be a judge on "Idol."
Since finishing behind Ruben Studdard and Clay Aiken at the end of the show's second season, Locke embarked on a solo career, releasing two albums on Curb Records. Locke recently started her own label, IAM Entertainment. Her first single, "Finally Free" came out on Tuesday. She plans to release another single this year and a full album early next year.