Stress and anxiety led to ‘genuine oversight’

and had consulted his GP about mental health problems the day before the alleged offence.

He added he was mistaken about where mobiles were allowed in the prison confines.

Three prison officers gave evidence claiming the lawyer had an “aggressive” manner as he was subjected to a search.

Dog handler John Park, 43, said the lawyer seemed “quite agitated” by his body language and the way he was responding to the staff.

He said: “He was asked more than once if he had a mobile phone in his jacket.

“He reacted strangely to be informed there was a phone.

“Normally someone would react with some shock and say:

Fairbairn was shocked when guards at HMP Addiewell found a phone in his jacket. ‘Oh my, I forgot it was there!’

“He didn’t make any excuse or apologise.”

Michelle Buggy, 36, a prison officer at Addiewell at the time, said a dog was present at the search.

She told the court: “He said something like: ‘ This doesn’t happen in any other prison.’

“Eventually he took his jacket off. He put it in the tray and I put it through x-ray machine.

“He stormed through the metal detector. He wasn’t very happy.

“The hands were going. His face was a bit flushed. He was moaning throughout the whole search, for about 10 minutes.”

Prison officer Craig Smith, 34, described Fairbairn as being “really uptight”. He added: “You just knew he was irate about something.”

Speaking in his own defence, Fairbairn said he had an aversion to dogs and was running more than 10 minutes late for a joint consultation with senior counsel Iain Duguid QC and a client charged with attempted murder.

De l i ve r i n g his ve rd i c t , summary Sheriff John MacRitchie ruled prosecutors had failed to show mobiles were banned in the public reception area where Mr Fairbairn was.

The Scottish Prison Service has strict rules on phones, banning them completely from visiting times and areas in an attempt to curb their use behind prison walls.

Mr Fairbairn has a wealth of criminal defence experience including defending driver Gary McCourt who killed two cyclist but escaped with a controversial sentence of 300 hours community service in 2013.

In 2 0 12 the Scottish Government made it a criminal offence for an inmate to have a mobile phone.

Despite this seizures continue. In 2015, 425 illegal phones were discovered after random prison cell searches.

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