Michael was one of four contestants axed from the ITV1 talent contest in a surprise quadruple elimination.
Brookstein argued that Gary Barlow made the wrong decision ditching Michael over Frankie Cocozza.
Writing in his London 24 blog, Brookstein said: "The X Factor's big twist was getting two good singers, James and Amelia, out while keeping in a couple of no hopers in the name of entertainment.
"The big stitch up was on James Michael. He entered The X Factor looking cool as a singer-songwriter and so they dressed him like a tramp, built a set to look like he was busking in a doorway and got him to sing a buskers' favourite Beatles number.
"It was a complete joke. Gary Barlow even described him as 'a professional busker'."
Brookstein added: "The poor lad was doomed while the limited Frankie Cocozza, who is being groomed as a 'popstar', talked his way through Ed Sheeran's 'A Team' like William Shatner 'singing' 'Rocket Man'."
Brookstein has been outspoken in recent years in his views about the show that brought him fame in 2004.
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