A MAN who was jailed for life after shooting dead a work colleague has launched a challenge to his conviction at the Court of Appeal.

Darren Jewell, 37, of John Street, Brightlingsea, gunned down 42-year-old roofer, Anthony Prickett, in St Osyth, in May 2011.

Jewell denied murder, but was convicted and jailed for life at Chelmsford Crown Court in January last year.

He is now appealing against the conviction in a Court of Appeal test case, revolving around the way trial judges should deal with a new "loss of control" defence to murder.

Jewell's appeal is being heard by the country's top judge, the Lord Chief Justice, Lord Judge, alongside four similar cases and is expected to continue for much of the week.

But today, the court heard that a deterioration in Jewell's mental health, resulting in him being moved to a secure psychiatric unit, could complicate his case.

Jewell's main grounds of appeal relate to the way the trial judge handled his claim of "loss of control", a murder defence which replaced the old one of provocation.