Mazher Mahmood, known as undercover reporter the ‘Fake Sheikh’, has been found guilty of tampering with evidence in the collapsed drugs trial of singer Tulisa Contostavlos.
The 53-year-old self-styled “king of the sting” is facing jail for conspiring to pervert the course of justice.
His driver Alan Smith, 67, was also found guilty of the same charge following a trial at the Old Bailey.
The pair was accused of conspiring to suppress evidence in the N-Dubz singer’s trial, which was later thrown out of court.
Mahmood met Contostavlos in a London hotel, posing as a film producer who wanted the singer to star in a Hollywood film.
Contostavlos was accused of arranging for Mahmood to be sold £800 of cocaine by one of her contacts.
As Smith, of Dereham, Norfolk, drove the former X Factor judge home to Hertfordshire, she allegedly spoke about a family member who had a drugs problem, the Press Association reports.
When the undercover reporter was interviewed by police more than a year later, Smith recalled the conversation.
But a day later, after speaking to Mahmood and emailing his draft statement, the singer’s anti-drugs comments were removed from it, the court heard.
At a pre-trial hearing, Mahmood denied being an “agent provocateur” or that he discussed the drugs conversation with Smith.
His defence team said that Mahmood “is not policeman, he is a journalist”, adding: “Securing convictions is not actually his job.”
After her case collapsed in July 2014, Miss Constavlos claimed to reporters she had been the victim of “a horrific and disgusting entrapment’’.
Mahmood claims to have helped put more than 100 people behind bars.
The prosecution asked for costs to be awarded totalling £37,929.
Both men are due to be sentenced on October 21.