Ellen DeGeneres has already set a few ground rules for her upcoming first season as an "American Idol" judge. First on her list: Contestants shouldn't talk back to her fellow panelist Simon Cowell.

"When you give your feedback, Simon, and somebody talks back to you, that's one thing that I just don't think I would tolerate," DeGeneres said in her first joint interview with Cowell in this week's issue of Entertainment Weekly. Not that he needs someone to come to his rescue, but DeGeneres has preemptively offered to back up her new co-worker. "It's unbelievable that people don't have any respect. They go on a show, they know they're going to be judged, that's what the entire show is about, and yet they tell you you're wrong. It's just rude and disrespectful and not OK. So that's not going to happen on my dime."

DeGeneres, who will not appear on the initial try-out rounds of "Idol" that kick off next Tuesday (January 12), told the magazine how she ended up taking the fourth slot on the panel and why she doesn't feel like she's replacing departed original judge Paula Abdul.

"My manager and agent called and said, 'There's interest. Is there interest on your side?' And I said, 'Yeah!' " explained DeGeneres, who will continue to do her popular daytime talker while sitting in with "Idol."

"I'm a huge fan of the show, but I didn't think for a second, 'Oh, Paula's gone; now I'll do this.' It didn't even occur to me. I was really surprised it didn't get out, because we talked about it for a while."

As she pulls double-duty, Ellen will have the advantage of inside scoop on each ousted contestant, though she said anything that could potentially hurt "Idol" will be off-limits on her talk show. "I don't want to give anything away," she said. "And if someone's a real jerk, I'm not going to expose them. I may change my mind if they really are a jerk."

Though some hard-core "Idol" fans were unkind to last year's new judge, songwriter Kara DioGuardi, DeGeneres said she's prepared for the barbs to be tossed her way. "I understand it," she said. "I was one of those people that was skeptical, like, 'Why are they adding a fourth judge? I don't understand this.' But I do think that Kara adds a lot to the show now. And also, it's not just a new judge. It's a new judge in the place of someone that they loved. I mean, a lot of people loved Paula, and I don't want to be the person that took Paula's job away from her. Which I wasn't. I'm not going to be able to please everyone. I gave up trying to do that a long time ago."

Unlike her appearance last year on "So You Think You Can Dance" — which drew some criticism when DeGeneres went for laughs over critiques — the comedian said she's not worried about being the first "Idol" panelist with no professional experience in the music industry. "It's not like I'm not a huge fan of music," she said. "That accounts for something. I've also been onstage, alone, trying to entertain an audience. I started in stand-up for 15 years. I know how important it is to reach that audience. So I can put myself in their position. It's not necessarily singing, but it's keeping an audience captivated."

Cowell jumped to DeGeneres' defense in the interview, saying that in the end, the only votes that really matter are the ones from the show's fans who dial in their picks. "We could hire four incredible vocal coaches tomorrow who know more about music than I'll ever know in a lifetime, and it will be the most boring show in the world," he said. "It's more than a scientific ability; it is your star power that is vital. Ellen has got a good instinct for people, and that is absolutely crucial."

The one topic they were reluctant to touch was the recurring rumor that Cowell may bolt "Idol" after this season. While DeGeneres has signed on for five years, Cowell's bid is up at the end of the upcoming season and many speculate that he'll quit after that to work on bringing his U.K. show "X-Factor" to American TV.

"If Simon goes, I go!" DeGeneres stated. "I will not be there without Simon."

Cowell, while joking that Ellen had put him in a "tricky situation," deftly dodged the elephant in the room. "I think right now we have to concentrate on the next season and just get through that and worry about everything else afterwards."

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