Who? Ben Rose, 51, senior partner and criminal department head at London firm Hickman & Rose.

Why is he in the news? He acted for celebrity Tulisa Contostavlos who had been charged with brokering a cocaine deal. She was alleged to have put the Sun on Sunday undercover journalist Mazher Mahmood (the ‘Fake Sheikh’) in touch with rapper Mike GLC, who supplied him with the drug in May 2013.

Contostavlos had denied the charges against her. Mike GLC (real name Michael Coombs) previously pleaded guilty to supplying cocaine.

Judge Alistair McCreath told the jury at Southwark crown court on Monday 21 July that the case could not continue because there were ‘strong grounds for believing that Mr Mahmood told me lies when he gave evidence to me [at a pre-trial hearing] on the 27th June.’

He explained that it was a ‘fundamental principle’ that the court could not allow itself to be party to improper conduct and, if he allowed the trial to continue, then ‘the court would be seen to be sanctioning or colluding in [improper] behaviour.’

He said: ‘This case cannot go any further.’

Thoughts on the case: ‘Investigative journalism has an important role in a liberal democracy, but do newspapers have the systems in place to protect the public interest? Fortunately, Tulisa’s ordeal is now over because the case will not be retried.’

Why become a lawyer? ‘A burning passion to make a difference.’

Career high: ‘12 January 2007, the day the Court of Appeal quashed my client Andrew Adams’ murder conviction. He had spent 14 years in jail for a crime he did not commit.’

Career low: ‘It was the firm’s first big case and I was so nervous my left hand was shaking and I had to hide it in my pocket. When I stood up to make the bail application, the Horseferry Road woman magistrate told me to ‘kindly take your hand out of your pocket when addressing me’. I wanted to crawl into a hole and stay there.’