News International's head of security today denied being part of a plot to shield Rebekah Brooks and the newspaper group from the Metropolitan Police's investigation into phone hacking.

Mark Hanna, suspended on full pay by the newspaper company when he was charged in May 2012, said he would not commit a crime for anyone.

Chief prosecutor Andrew Edis challenged Mr Hanna on the alleged plot to hide bags belonging to Mrs Brooks's husband, Charlie, from the police on 17 July 2011.

During his three days in the witness box, Mr Hanna explained that he agreed to look after Mr Brooks's briefcase on the morning of 17 Sunday, when the Brooks's and their security team drove from Oxfordshire to London, where Mrs Brooks was arrested.

Mr Hanna then agreed to keep from police a Jiffy bag and a laptop hidden behind bins in the car park below the Brooks's London flat because, he told the court, they contained embarrassing (though legal) pornography.

The property was returned to the flat later, along with delivery of pizza - only to be hidden behind bins again and discovered the following day by a cleaner.

Mr Hanna told the Old Bailey that he had never heard the term used by members of his security team to describe the weekend's events: "pizzagate."

When told that "gate" was added to cover-ups such as Watergate, Mr Hanna, formerly head of security at the Tower of London, told the Old Bailey: "The first Watergate I came across was the Water Gate at the Tower of London..."When Mr Edis suggested that moving Mr Brooks's property around on day his wife had been arrested would have been "dangerous" and must have been done "for some real purpose," Mr Hanna replied: "I don't understand the word 'dangerous'. I wouldn't commit a crime for anyone."

As far as I believe what I did was legal."

Mr Edis challenged the idea that that day's events were "spur of the moment", to which Mr Hanna replied: "What I have told you is absolutely true."

Mr Hanna and Mr and Mrs Brooks deny conspiring to pervert the course of justice. The case continues tomorrow.