Mariah Carey's performance on the American Idol finale last night has resulted in some accusations of lip-synching.
The judge took to the stage to perform a medley of her biggest hits, and some viewers on Twitter weren't convinced that she was singing live.
The mash-up included Hero, Make It Happen, My All, Vision Of Love, We Belong Together and her new tune Beautiful.
One viewer wrote: "Mariah Carey needs to practice her lip syncing. She on American Idol right now making a fool of herself"
Another blasted: "Can we please discuss @MariahCarey's stellar lip syncing last night on #americanidol"
Mariah Carey promotes American Idol (WENN)
"I want a congressional investigation into Mariah Carey's horrid lip syncing last night. And that Mattel dress of hers," raged one Idol viewer, and a fourth wrote: "Mariah Carey lip syncing parts on the Idol finale? Kind of ironic that she critiques live performances when she can't even do it herself."
Another jibe reads: "Mariah Carey was lip syncing last night and still sounded horrible...how TF?"
Someone attempted to diffuse the situation by commenting on YouTube: "It was NOT lip synched it was dubbed!
"Mariah performed each song 3 times for American Idol to get the best versions of each song, where then the producers would put together each piece and make it all one song. It was HER voice, completely LIVE! She IS the best! *All info is from people who attended the LIVE taping of her performances!"
Watch the performance below and judge for yourself.
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