The star rainmaker fighting a £450,000 Financial Services Authority fine for allegedly leaking inside information could have "made up" information in an email at the centre of the case.
Ian Hannam, the former JPMorgan chairman of capital markets, made the admission when he took the stand in his case against FSA successor body the Financial Conduct Authority yesterday afternoon.
The penalty came two-and-a-half years after the FSA launched an investigation that ultimately centred on two emails that the regulator claimed revealed price-sensitive details about a client, Heritage Oil.
Mr Hannam denies claims that he was leaking information in the autumn of 2008 regarding Heritage Oil, but in emails to Kurdistan oil minister Ashti Hawrami he said that the company had "found oil" and had been approached by a potential buyer.
Under cross-examination from FCA QC Richard Boulton, Mr Hannam said that he was "either making it up or putting a spin on it to get a meeting [with Mr Hawrami]". Earlier in his testimony, Mr Hannam had said that he could not "recollect the circumstances i sent that email. I've been trying to put it together."
The case centres on whether Mr Hannam was simply trying to flush out an offer for Heritage by sending the emails. Mr Hannam was the FSA's prized scalp on its crackdown on City practices, though he was not stripped of his banking licence.
The former SAS reservist left JPMorgan last year after the FSA made his fine public. He had already been censured in an internal investigation at the bank, which was run by 14 lawyers from Linklaters.
However, he was found to have fallen short of the bank's standards rather than to have leaked inside information. Mr Hannam was put on warning and even forced to take "email training".
Mr Hannam, known in the mining world for advising on the creation of empires like BHP Billiton and Xstrata, resigned shortly after the FSA made the fine public, vowing to clear his name.
The case continues.