"This has been a horrendous two years for Mr. Merkin and his family, " said Mr. Merkin's attorney Andrew Levander.

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The problem with categorising Mijailovic is that he was "a threshold case", Sten Levander, a forensic psychiatry professor from Malmo University Hospital, told BBC News Online.

BBC: NEWS | Europe | Doctors split over mind of a killer

In addition, Prof Levander says, the team assessing the killer was not run by the most senior psychiatrists available, because "many had been involved with the media" in the wake of the murder, and were not seen as impartial.

BBC: NEWS | Europe | Doctors split over mind of a killer