A senior police officer tampered with evidence just over an hour after his boss was cross-examined at the inquest into the death of Jean Charles de Menezes, it was claimed.
But the Special Branch surveillance officer, named as Owen, denied allegations he was part of a "cover-up" as he returned to the witness box.
Owen is being investigated by the Independent Police Complaints Commission after last week admitting removing a line from his notes during proceedings.
The deleted line claimed Deputy Assistant Commissioner Cressida Dick said the suspect could "run onto Tube as not carrying anything".
As Owen, flanked by his lawyer, was recalled to the inquest, he was asked by Michael Mansfield QC, for the de Menezes family, if he had attempted to hide the changes he had made.
He replied: "That's incorrect sir."
He also said he was not under pressure from "management" to change his notes.
He added: "I wasn't getting concerned sir and no-one expressed concerns to me from management, if that is what you are getting at."
Mr Mansfield said computer records showed Owen had edited his notes at "11.52GMT" on October 7.
Mr Mansfield said the notes were edited less than an hour-and-a-half after Ms Dick was questioned about Scotland Yard's policy of letting suspects on to the Underground.
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