Meet the father who forgave his son for murdering his family.

He was charming, intelligent and interesting.

In the hour I spent in Bart Whitaker’s company, I couldn’t help but find him likeable. And that made me extremely uncomfortable. Like most journalists, I like to think I’ve developed an excellent bullshit detector. So how could I be charmed by a man who organised the murder of his entire family?

I met Bart Whittaker where he now lives – on death row in the Polunsky Unit, a notorious Prison in Texas. I knew all about his crime before I met him, and I’d spoken to his father Kent – the only member of the family to survive Bart’s murder plot – a beautiful man, who has somehow found the faith and grace to forgive his child for orchestrating the brutal murder of his wife and youngest son.

On December 10, 2003 the entire Whitaker family – Kent, his wife Tricia, and sons Bart and Kevin – were gunned down inside their home in Sugarland, Texas, by a masked man who had been waiting inside for them. Kevin died instantly. Tricia died on the way to the hospital. Bart and Kent survived.

It didn’t take detectives long to figure out Bart was the mastermind. He’d convinced one friend to be the shooter and another to drive the getaway car. The whole thing was planned right down to the detail of Bart being shot in the arm – enough to make him look like a victim, without killing him.

Detective Marshall Slot was in charge of the case. He recalls having to tell Kent what he knew: “As politely as I could tell him, I said ‘well, your son’s a monster. He’s responsible for this. All the evidence points to him’.” Kent refused to believe it.

Bart had been portraying himself as the perfect son. The night of the shootings, the family had been out celebrating his graduation. But it was all a lie. He had dropped out of college and was partying hard. And despite the family happy snaps, he was miserable inside and resented his family.

Even once his son was charged, Kent stood by him. He did so throughout the trial, and as the sole surviving victim he even argued against the death penalty – but it wasn’t to be.

I was hard on Kent. How did he not see the murders coming? How could he forgive his son? And given Bart had lived such a duplicitous life – how could he possibly believe his son had changed?

I met Bart 12 years after his crime. He’d had a lot of time to think. Not only about the murders, but about how his father had chosen – even before knowing he was behind the shooting – to forgive whoever was responsible. I saw a little of what his father saw: a lost loner who never fit in, who refuses to make excuses for what he calls his awful crime.

I met him behind glass, after walking through a metal detector and behind several locked iron doors on death row. We talked through a telephone. His handcuffs were removed for the conversation but he was still in his prison issue clothing. And he was pale. 23 hours a day in an isolation cell for years on end can do that. But he was sharp, articulate and at times funny. I had gone there wanting to hate him, but I couldn’t.

So why did he do it? “I didn’t know how to relate to them and they did not know how to relate to me and they did not even realise there was a deficit and that that was sort of the problem. I guess that’s really the root of all this that I felt like I was drowning in a very public pool and nobody was noticing.”

I pointed out many people felt that way and didn’t resort to murder. I asked how he convinced two other people to go along with his plan. “We were all really, really miserable human beings and this was sort of our game of chicken we were playing with each other, how evil can we get, you know”, he said.

A game of chicken. With his family’s life.

“Yeah it’s awful right and I get I get it. You know, trust me I get it. There’s so many things that a person in my position can say here, but they all sound like excuses and I’ve never done that.”

Since being in prison, psychiatric tests have revealed Bart suffers from Asperger’s, ADD and psychotic disorders with paranoid, narcissistic and antisocial features. At the time of the murders he was also heavily involved with drugs and alcohol.

To this day, his father Kent visits Bart most weeks. True to his Christian faith, Kent has forgiven his son. He is proud of his progress, the artwork he does in prison, and the blog that he writes. “It’s important to recognise that forgiving somebody it isn’t justifying what they did,” he says. “It isn’t saying ‘I forgive you so it’s alright’.” He does think Bart has changed. And, Kent says, the act of forgiveness has helped him heal some of his own emotional scars.

But there is no convincing the other man who had to live through the tragic trail left by Bart, Detective Marshall Slot, who says Bart deserves the death sentence he was given. “I believe wholeheartedly that Bart Whitaker’s a sociopath.”

I ask – dreading the answer – whether he thinks I was taken in.

“I believe you could have been taken in by Bart Whitaker”, he says, deadpan. “He’s charming, intelligent, engaging. My personal feeling is that he gave you what you wanted to hear. ”

Bart Whitaker is a murderer and a self confessed liar. He somehow jumped a forbidden gulf. Striking at what he thought was the cause of his angry, alienated life, he calmly and calculatingly plotted the murder of his family.

The man he hurt the most has made his own leap of faith. After already losing so much, still offering forgiveness and love to a son who is also destined to die.

It’s a test few of us would like to face.