A surgeon who served a jail sentence over the death of a patient from Northern Ireland at a private hospital is asking leading judges to overturn his "unsafe" conviction.
David Sellu, now 69, was convicted of gross negligence manslaughter in November 2013 and handed a prison term of two-and-a-half years at the Old Bailey.
He was present at the Court of Appeal in London yesterday to challenge his conviction over the death of father-of-six James Hughes.
Armagh man Mr Hughes (66) died at the Clementine Churchill Hospital in Harrow, London, after falling unexpectedly ill following knee surgery.
The retired builder had a planned left knee replacement on February 5, 2010. The operation went well, but while recovering from surgery he developed abdominal pain and was transferred to Sellu's care.
At the start of the conviction challenge, Mark Ellison QC, for Sellu, told Sir Brian Leveson, Lord Justice Irwin and Mr Justice Globe, that Sellu, a "respected consultant colorectal surgeon", treated Mr Hughes between February 11 and 12, 2010. It was the standard of the doctor's care to Mr Hughes over a period of approximately 25 hours which formed the basis of the case against him.
Mr Ellison said the prosecution case at trial "essentially reflected" the opinion of its two medical experts "as to Mr Sellu's care having been in a number of respects grossly negligent, in the context of a dramatically increasing risk of Mr Hughes dying over a 25-hour period leading up to the operation".
He said the "essence" of the prosecution case was that the doctor should have performed an operation to repair a perforated bowel "at a much earlier time".
After surgery Mr Hughes was transferred to the intensive care unit but he died on February 14, 2010.
Mr Ellison said that Sellu, of Hillingdon, who served 15 months before being released in February last year, submitted that "his conviction for gross negligence manslaughter is unsafe" on a number of grounds.
He told the judges that there was now new evidence "undermining the prosecution case as to Mr Hughes's increasing risk of mortality and the need for an earlier operation to have been carried out".
The QC argued that the fresh evidence "casts serious doubt upon the accuracy and reliability" of the prosecution evidence. It is also argued on Sellu's behalf that the trial judge "misdirected" the jury in certain respects, including a claim that he "failed adequately" to explain to the jury the meaning of gross negligence.
Mr Ellison, in written submissions before the court, states: "This was a highly complex gross negligence manslaughter case throwing up a plethora of expert issues."
Sir Brian indicated that judgment would not be given immediately at the conclusion of the proceedings, expected to last two days, as the case involved "important issues both of law and fact".
The appeal is being contested by the prosecution. At hearing.