Spare a thought for Lisa Osofsky, the embattled US lawyer who heads the Serious Fraud Office. It never rains but it pours.

The watchdog’s ‘successful’ prosecution of four men for bribery following its Unaoil investigation appears to be falling apart – in no small part due to Osofsky’s contacts with former DEA agent David Tinsley, a ‘fixer’ working for the family behind the energy company.

The Court of Appeal has quashed two of those four convictions over the SFO’s ‘serious’ failures to disclose information about those contacts – which include Osofsky texting to say she was ‘super- honoured’ to meet Tinsley. Yikes.

When the former FBI lawyer became SFO director, there was speculation Osofsky might import a more American style. If that is so, the cultural exchange has not been one-sided. She has also learned how to deftly parry awkward questions from MPs, in the manner of a seasoned mandarin.

Osofsky deployed the ‘Sue Gray defence’ with expertise at the Commons justice committee, sheltering behind former High Court judge Sir David Calvert-Smith’s review of the Unaoil investigation.

How much will these two quashed convictions cost the public purse? The SFO was ‘very grateful’ to Sir David and is being ‘very cooperative’, she replied.

Alas, as there is an ongoing review, ‘I am not in a position to answer anything further’, she added (where have we heard that before?).

MPs pointed out that the Court of Appeal’s ruling was a matter of public record. To no avail. Osofsky, clearly a stickler for the rules, did not want to ‘impinge’ on Sir David’s work.

What about the ‘discrepancy’ between the accounts given by her and Tinsley regarding how many times they had met? ‘I am going to gladly and willingly explain everything to Sir David Calvert-Smith,’ said Osofsky.

And so the long day wore on...

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