Tulisa Contostavlos said her life had been "ruined" for the last year by what she called "entrapment" from an undercover reporter working for the Sun.
Speaking outside Southwark Crown Court, the singer and former X Factor judge called on the police and the Sun's publishers, News UK, to look into Mazher Mahmood's conduct.
The judge in the case said there were "strong grounds" to believe Mahmood had "lied" and given "entirely inconsistent" evidence.
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A man has been charged with stealing his own barrister's mobile phone at a magistrates' court in Bexleyheath, Kent.
A rapist who attacked an 80-year-old woman in her own home has been jailed for life, as police urge other victims to come forward.
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