Mr Robinson, a director of Kendal Calling, told thejury at Carlisle Crown Court he hired Mr Piper after realising that the event had grown so big that an experienced health and safety professional was needed.
The officials acknowledged to CNN that Starr's calling Cockell before the grand jury has been "disruptive, " but they insist they want Cockell to resume his duties as soon as he is done answering Starr's questions.
The adviser said the Bush campaign will comply with the subpoenas from the grand jury sitting in Washington, callingthe latest development a "good sign" that investigators will get to the bottom of what happened.