The letter, signed by Hogg and vice-chairman Bill Withers, said a formal consultation was not needed because no services would be lost and access would not be affected.
Pinkerton said: “It is extraordinary that a project of this scale could proceed without a formal NHS public consultation.”
He said the relocation was “the most significant change to healthcare provision in Surrey Heath for a generation”.
He added: “My letter asks what evidence supported that conclusion at the time.”
In a response, Hogg said the NHS had considered whether wider public consultation was necessary.
He said officials decided it was not required.
Hogg said the plans did not involve a major loss of access for patients.
He said the search area remained within five miles of the current hospital.
“If there had been an obvious disadvantage at that time to patients, then I might have felt differently about the issue,” he said.
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