Image copyright ALAMY

Singer-songwriter Steve Earle describes how Truman Capote's account of a murder, In Cold Blood, captured his imagination when he was a boy, and inspired a lifelong opposition to the death penalty. He read the book after he saw the movie adaptation (pictured above) at the drive-in.

I was 11 years old when Truman Capote's groundbreaking "non-fiction novel" In Cold Blood was published and while I had always read well above my grade level in school I wasn't quite that precocious.

A voracious consumer of science fiction, I subscribed to all the monthly anthologies and I could rattle off a complete bibliography of the works of Robert Heinlein and Isaac Asimov, but I knew the name Capote only in some vague connection to the film version of Breakfast at Tiffany's starring Audrey Hepburn, my mother's favourite.

Movies were a family affair in the Earle household, the seven of us piling into a Ford station wagon bound for the Towne Twin Drive-in Cinema. "A dollar a carload," the sign announced. Dad cheerfully handed over his dollar and was directed to an empty space where he parked, rolled down the window and reached out to lift the speaker from its cradle and hang it inside the door. It was a singularly American cultural experience.

If it was released in the '60s then odds are I saw it from the back seat of the family car or, as I got older, a row of metal chairs on both sides of the common concession building that separated the dual screens. My dad was anything but democratic about the choice of film but we were welcome to take in the feature on the opposite screen if it was more to our taste.

On one such family outing in 1967, when I was not quite 13 years old, the Earle family arrived a little late, just in time to to catch the cartoon. My parents assumed us kids would want to see the spy thriller, In Like Flint. They were there to see Richard Brooks's film adaptation of In Cold Blood.

Image copyright Getty Images Image caption Truman Capote (left) with film director Richard Brooks

I'd seen the James Bond wannabe already, with a friend's family, the weekend before, so rather than go through the snack bar to the other screen with my brother I found myself a seat on the In Cold Blood side of the concession stand, not expecting much.

Find out more Steve Earle discusses In Cold Blood in BBC Radio 3's The Essay, The Book That Changed Me, on Monday 19 January at 22.45 GMT

But from the moment that Robert Blake, as Perry Smith, appeared on the screen, a cracked-mirror Elvis in a leather jacket and child-sized motorcycle boots I was riveted, right up until his stunted silhouette bobbed at the end of a rope to the beat of a stuttering amplified heartbeat.

It was an eerily quiet ride back to the house that night. My parents had no idea that I had seen the same film they saw because not a single word passed between any us all the way home. I awoke the next day morbidly obsessed - which truth be told, was not totally out of character for me.

The writing of In Cold Blood

Image copyright Getty Images Image caption Truman Capote, photographed in 1966

Truman Capote (1924-84) was inspired to write his "non-fiction novel" after seeing a brief report on the Clutter family murder in the New York Times in 1959

Capote spent several years researching the case - helped by his friend, the novelist Harper Lee - during which time he talked to most of the Clutters's neighbours, and eventually to the murderers themselves

In Cold Blood: A True Account of a Multiple Murder and Its Consequences, first published in 1965, charts the story of the case from the crime to the execution by hanging of Hickock and Smith - it was both a critical and commercial success

A few years earlier, when all my friends were painstakingly assembling grotesquely detailed plastic figures of Frankenstein's monster, the Wolfman and the Phantom of the Opera, I preferred the even creepier replicas of the guillotine, electric chair and gallows complete with working trapdoor. I built them and put them through their lethal paces. Thankfully, it was only a phase that filled some blank space in me that no longer existed as soon I learned to play a few chords on a guitar and discovered girls. But that night at the movies my ghoulish nine-year-old self had been awakened by a chilling revelation.

There were still places in the world, not very far from where I lived, where men still hung other men by their necks until they were dead,

I had to learn everything there was to know about this hanging that had taken place in Kansas only two years before. The ads all said that the film was "based on a bestseller". I had to find a copy of that book and read it for myself.

But where? There were no book stores in my tiny hometown and it seemed to me very unlikely that even the high school library would possess a copy. In the end, I didn't have to look even that far.

Image copyright Flickr/University of Maryland

I was actually looking for an open pack of cigarettes to nick when I came across it in my mother's handbag. The paper cover was white, the title emblazoned in bold black letters above the author's name in blood red. In Cold Blood by Truman Capote. I took both, the book and the smokes and devoured them in three days.

I was reading it in school, when I would have been better served reading anything else as Perry and his pal from the penitentiary, Dick Hickock rolled across the high plains in a jet-black Chevrolet plotting the ultimate "score". It was a sure thing, according to a former cellmate of Dick's. Said he used to work for a rich farmer in Holcomb, Kansas. Didn't trust banks. Kept a safe stuffed with cash. But first a stop for a few supplies.

The first purchase was a pair of rubber gloves; these were for Perry, who, unlike Dick, had neglected to bring old gloves of his own.

They moved on to a counter displaying women's hosiery. After a spell of indecisive quibbling, Perry said, "I'm for it."

Dick was not. "What about my eye? They're all too light-colored to hide that."

"Miss," said Perry, attracting a salesgirl's attention. "You got any black stockings?" When she told him no, he proposed that they try another store. "Black's foolproof."

But Dick had made up his mind: stockings of any shade were unnecessary, an encumbrance, a useless expense ("I've already invested enough money in this operation"), and, after all, anyone they encountered would not live to bear witness. "No witnesses," he reminded Perry, for what seemed to Perry the millionth time.

My nose was buried in the book at the dinner table, much to the chagrin of my father who was the cook in our house, as I got to know the doomed Clutter Family intimately through the eyes of Nancy's boyfriend, Bobby, the last to see them alive.

"So we sat around like any other night - Nancy and I on the couch, and Mr Clutter in his chair, that stuffed rocker. He wasn't watching the television so much as reading a book... Once he went out to the kitchen and came back with two apples; he offered one to me, but I didn't want it, so he ate them both. He had very white teeth; he said apples were why. Nancy - Nancy was wearing socks and soft slippers, blue jeans, I think a green sweater; she was wearing a gold wristwatch and an I.D. bracelet I gave her last January for her sixteenth birthday - with her name on one side and mine on the other...

After the sports ended, that was ten-thirty, and I got up to go. Nancy walked me out. We talked a while, and made a date to go to the movies Sunday night... Then she ran back to the house, and I drove away... Only now when I think back, somebody must have been hiding there. Maybe down among the trees. Somebody just waiting for me to leave."

Image copyright AP Image caption The Clutter family home in Holcomb, Kansas

By flashlight, so as not to disturb my brother, I was horrified by the carnage of the crime scene as witnessed by the local sheriff:

About then we heard footsteps. Coming up the stairs from the basement... Turned out to be Wendle Meier, the undersheriff... the sheriff told him - and it was sort of pitiful: "Wendle, I don't know what to make of it. There's two bodies upstairs." "Well" he said, Wendle did, "there's another one down here." So we followed him down to the basement... Kenyon was over in a corner lying on a couch. He was gagged with adhesive tape and bound hand and foot, like the mother - the same intricate process of the cord leading from the hands to the feet, and finally tied to an arm of the couch. Somehow he haunts me the most, Kenyon does. I think it's because he was the most recognizable, the one that looked the most like himself - even though he'd been shot in the face, directly, head-on.

Meanwhile, as I rode the bus to school on the second day, the outlaws were headed for Mexico… but not before passing a string of bad checks because when everything was said and the deed was done, Dick's cellmate Floyd had made the whole thing up. There was no safe in the Clutter home and the pair had wiped out an entire family for 40-some-odd dollars and a dime store radio.

I held some sympathy and... genuine empathy for Perry Smith and Dick Hickock, even though no two characters less deserving of either had ever been committed to paper

"O.K." Dick said. "Maybe I had some wrong information."

"Hallelujah."

"But on the whole it was perfect. We hit the ball right out of the park. It's lost. And it's gonna stay lost. There isn't a single connexion."

"I can think of one."

Perry had gone too far. He went further: "Floyd - is that the name?"... Perry observed with some misgiving the symptoms of fury rearranging Dick's expression: jaw, lips, the whole face slackened; saliva bubbles appeared at the corners of his mouth. Well, if it came to a fight, Perry could defend himself. He was short, several inches shorter than Dick, and his runty, damaged legs were unreliable, but he outweighed his friend, was thicker, had arms that could squeeze the breath out of a bear. To prove it, however - have a fight, a real falling-out - was far from desirable. Like Dick or not... it was obvious they could not now safely separate.

Image copyright AP Image caption Richard Hickock and Perry Smith, who were executed for the murders

The pair would make it to Mexico during my sixth period study hall but lack of funds forced them back across the border to zigzag from one end of the country to the other leaving behind a coast-to-coast trail of worthless checks including a string as close to the scene of the crime as Kansas City. In the end it would indeed be Dick's buddy Floyd who would give them up after reading about the killings in the newspaper. An all-points bulletin was issued and the murderers were pulled over in a stolen car in Las Vegas, extradited to Kansas, tried, convicted and sentenced to be hanged with lead investigator Alvin Dewey and yours truly in attendance:

Steps, noose, mask; but before the mask was adjusted, the prisoner spat his chewing-gum into the chaplain's outstretched palm. Dewey shut his eyes; he kept them shut until he heard the thud-snap that announces a rope-broken neck. Like the majority of American law-enforcement officials, Dewey was certain that capital punishment is a deterrent to violent crime, and he felt that if ever the penalty had been earned, the present instance was it. The preceding execution had not disturbed him, he had never had much use for Hickock, who seemed to him "a small-time chiseller who got out of his depth, empty and worthless". But Smith, though he was the true murderer, aroused another response, for Perry possessed a quality, the aura of an exiled animal, a creature walking wounded, that the detective could not disregard. He remembered his first meeting with Perry in the interrogation room at Police Headquarters in Las Vegas - the dwarfish boy-man seated in the metal chair, his small booted feet not quite brushing the floor. And when Dewey now opened his eyes, that is what he saw: the same childish feet, tilted, dangling.

I had never read anything remotely like it. I had enough science fiction under my belt by the time I was 12 to understand that words could challenge me to think, to consider ideas and attitudes that would have never occurred to me otherwise, but this writer was dragging me around by the heartstrings and it was that meeting of my heart and my mind that would ultimately coalesce in my decades-long involvement with the campaign against the death penalty around the world. But it all began that day when I finished reading and I closed the book that changed me and discovered, much to my surprise, that despite my compassion for the Clutters and my horror at the atrocity inflicted on them, I held some sympathy and perhaps even more profoundly confusing, genuine empathy for Perry Smith and Dick Hickock, even though no two characters less deserving of either had ever been committed to paper.

Why?

The power of intellect and humanity flowing from heart to hand to pen to page.

And I could put myself on Death Row, alongside two cold-blooded murderers because Truman Capote could.

About Steve Earle

Image copyright Ted Barron

US country singer and songwriter - born in Texas, his own hits include Copperhead Road, I Ain't Ever Satisfied and My Old Friend The Blues, and his songs have been covered by artists such as Johnny Cash, Emmylou Harris and The Proclaimers

Has also acted, most notably as a recovering heroin addict and drug counsellor in detective series The Wire

Politically outspoken in his music, Earle was an opponent of the Iraq war and has campaigned against the death penalty in the US

The Book That Changed Me: Steve Earle on In Cold Blood will be broadcast on BBC Radio 3 at 22:45 GMT on 19 January - or catch up on BBC iPlayer

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