David James Smith, who has also worked for the Criminal Cases Review Commission, did a face-to-face interview in 2010 with the man who was convicted of murdering five members of his family in 1985. Audio of the interview features in a new Sky Crime documentary tonight, which “will help people make up their minds” on the case, Mr James Smith says. Bamber shot dead his adopted parents Nevill and June inside White House Farm, along with their adopted daughter Sheila Caffell and Sheila’s six-year-old twin sons, Daniel and Nicholas Caffell.
He is serving a full life term in HMP Wakefield but has always professed his innocence.
“It was a weird day,” Mr James Smith said of meeting Bamber. “I thought he might make my flesh creep but it wasn’t really like that. On the face of it, he was quite human, quite recognisable as a person, like someone you might meet in a pub.
“His eyes filled up with tears when I asked him what he missed about the outside world.
“And yet at the same time, there is the real possibility that he carried out this appalling, clinical, callous murder of his entire family.
“He reminded me of an ageing accountant, his hair slightly greying, and a little bit paunchy.”
The most “surreal experience” was when the prison provided food: “We stopped for lunch and the prison had made sandwiches for us. So we went outside, and we sat down with Jeremy, a couple of prison officers and all had sandwiches with a mass murderer. It was a very odd experience.”
Mr James Smith added: “My job was to draw him out and let other people make up their minds. He had strong opinions about members of his family who he said had conspired against him.
“They, of course, see him as a callous, greedy killer who wanted to secure a £400,000 inheritance.”
Asked if he believed what Bamber was saying, he replied: “I had no reason to disbelieve what he was saying.”
Bamber is mounting a new case review, now claiming there were two gun silencers at the murder scene, not one.
It was Sheila’s blood on a silencer and the weapon’s length which helped convict him, as it ruled out the possibility of her being the killer.
Asked if it was now too hard to prove or disprove anything in the case, Mr James Smith said: “I think that’s probably true. The evidence bears different interpretations depending on your point of view.
“But these anomalies exist and there is doubt and hope for Bamber.”
He added: “Bamber turned 60 this year and he’s never going to give up.These cases have a habit of coming back over and over again.”
• The Bambers: Murder At The Farm, Sky Crime and NOW, tonight at 9pm