Mary J. Blige: Judging Idol Was "Really Hard"

Credit: Michael Becker/Fox

Judging American Idol is no easy task. Just ask Mary J. Blige.

"It was so much fun, but it was hard," Blige, 39, who appeared on the show Jan. 13, told at BET Honors in Washington, D.C. on Saturday.

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"It was really hard, you know, because you didn't want to be bursting out into laughter," added Blige, who fought laughs a few times. "And you have to be honest. I had to be honest with people."

As for wannabes who didn't approve of her commentary, Blige said, "Someone got upset, but that's their problem, not mine." (Hopeful Lamar Royal threw a temper tantrum and called her a b*tch.)

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Blige admitted she "doesn't know" what the show will be like once Simon Cowell leaves after this season.

"It's hard to predict... I hope they get someone who tells the truth," Blige told Us. "Simon told the truth."