Pop star Tulisa Contostavlos's disapproval of drugs was "airbrushed out" so undercover reporter Mazher Mahmood could be the "swashbuckling hero", a court has heard.

Mahmood, 53, and his driver, Alan Smith, 67, are on trial at the Old Bailey accused of tampering with evidence in the collapsed drugs trial of the former X Factor judge, who lives in Friern Barnet.

The court has heard how the Sun's so-called Fake Sheikh had a boozy meeting with the singer at the Metropolitan Hotel in London, posing as a film producer keen to discuss a role alongside Hollywood star Leonardo DiCaprio.

Miss Contostavlos had allegedly arranged for Mahmood to be sold half an ounce of cocaine by one of her contacts for £800 in May 2013.

But the N-Dubz star's trial was thrown out of court after Smith changed his police statement to remove comments she allegedly made expressing disapproval of hard drugs.

She had allegedly said she had a family member with a drug problem as Smith drove her home to Potters Bar in Hertfordshire after the meeting with Mahmood.

Mahmood, of Purley, south London, and Smith, from Dereham, Norfolk, deny conspiring to pervert the course of justice.

Both defendants have declined to give evidence in their defence.

Prosector Sarah Forshaw QC said in her closing speech: "If they were innocent men with nothing to hide, wouldn't they be shouting it from the rooftops?"

She told jurors: "When you put them all together, they altogether lead you to the compelling inference that these two men put their heads together to change that statement - a compelling inference that demands an explanation and you have had none."

The lawyer suggested that Mahmood had wanted to "show off" to his employers and prove that he "deserved the title of King of the Sting".

But his methods had been put on trial over the question of entrapment, which he denied.

Pre-trial legal argument risked him being "exposed" as a "trickster" rather than the "swashbuckling hero" he wanted to be, said Ms Forshaw.

Smith's initial statement to police which included the pop star's anti-drugs comments had posed a problem for the journalist, the court heard.

And so Miss Contostavlos's disapproval of hard drugs was "airbrushed out" after Smith emailed his statement to Mahmood, Ms Forshaw said.

She added: "You may think these men have concluded their best chance of being found not guilty is to say nothing."