Tulisa was accused of hitting the new TOWIE star at the festival in Essex during a drunken confrontation.
The 26-year-old’s friend Gareth Varey was cleared of threatening behavior towards the blogger.
Judge Angus Hamilton gave the ruling at Stratford Magistrates Court in East London earlier today.
According to reports, Tulisa has been fined £200 for the assult.
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The ‘guilty’ verdict comes just days after Tulisa’s most recent court case collapsed dramatically after the judge said that there were ‘strong grounds to believe’ that undercover reporter Mazher Mahmood had ‘lied’ under oath.
Tulisa was charged with helping a friend supply cocaine and was filmed by an undercover journalist as she claimed she could ‘sort out’ a drugs deal.
According to Tulisa’s lawyer, the singer believed that the undercover journalist was a Hollywood movie producer and that she would be offered a part in a film starring alongside Leonardo di Caprio.
Mahmood wrote up the report for The Sun on Sunday last year, just days before it was announced Tulisa would not be returning to her seat on the X Factor judging panel.
Mahmood has since been suspended from the tabloid.
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