On the evening of 19 November 1998, the body of a Colombian man, Julian Colon, was found in the boot of an abandoned car in Kansas City, Missouri. His hands, feet and eyes had been bound with duct tape, and he had been shot in the head. Cartel drug lords, who were importing cocaine, via Mexico, into Texas and distributing it onwards from Kansas City, were convinced that Colon had stolen $300,000 from them, and had him executed.

Ten days later, a Colombian immigrant, said to be an enforcer for the cartels, German Sinisterra, was arrested. Under interrogation, he confessed, saying that he had been told by the traffickers to fly to Kansas City from his home in Dallas, and to undertake a job for a fee of $1,000. He was afraid to say no: most of his family was in Colombia, vulnerable to reprisals. Sinisterra described how Colon was lured to a meeting by two cartel associates, where he was bound and beaten, before Sinisterra was ordered to shoot him.

Sinisterra went on trial for first degree murder in Kansas City in December 2000. His case was not heard in the local state court, but in the separate federal system, run by the Department of Justice – the forum for some of the most serious cases, many involving organised crime or terrorism. The prosecution asked the court to sentence him to death.

Leading his defence was Frederick Duchardt, a Kansas City attorney appointed by the judge. American death penalty trials consist of two successive phases. In the first – the “guilt phase” – the jury decides whether the prosecution has proven its case beyond reasonable doubt. Then, in the “penalty phase”, the same lawyer presents the case, and the same jurors determine whether the prisoner should be sentenced to death or life imprisonment.

As Sinisterra’s guilt was not disputed, what sentence he would receive was crucial. Duchardt’s plea for Sinisterra in the second, penalty stage focused on evidence that he was a caring husband and father, beloved by his family in Texas, and his relatives still in Colombia. Duchardt revealed that Sinisterra was raised in poverty in the port city of Buenaventura, had emigrated in his late teens and worked in construction. His wife, a nurse named Michelle Rankin, told the court he was “loving and caring”. They had two small children, and he also took care of his daughter from a previous relationship. His mother-in-law testified that all her family adored him. Videotapes in Spanish recorded by family members in Colombia spoke of his generosity. His nine-year-old said that her father played with her, took her to school, and had bought her a Bible story book.

None of this made much impact. The jury deliberated for less than a day before sentencing Sinisterra to death.

Since Sinisterra’s sentencing, three more of Duchardt’s clients have been condemned to death: Wes Purkey, Lisa Montgomery, and, most recently, in 2014, Charles Hall. Out of seven federal death trials, four of Duchardt’s clients have received the death penalty, two have been handed life sentences and one has been acquitted after an appeal and a retrial. This tally means that Duchardt has had more clients sentenced to death in federal court than any other defence lawyer in America.

The lawyers appealing against the death sentences of Sinisterra, Purkey and Montgomery have all separately argued that their sentences should be quashed because Duchardt’s performance was “deficient”, and that his failure to present critical mitigating evidence amounted to what US law terms “ineffective assistance of counsel”. (Hall’s appeals have not yet started.)

Duchardt finds these allegations preposterous. A tall, softly spoken figure of 64, he has wispy, greying hair and a droopy moustache. Not for him the lawyer’s uniform of white shirt and dark suit: both times we met, he wore jeans and an old sweater. I got the impression he wanted to be liked, generously suggesting we set aside at least two hours for our meeting on my first day in Kansas City.

When it came to specific claims about his own conduct, he stiffened and, palpably defensive, declined to go into details. The reason his clients got the death penalty, he said, had nothing to do with his performance, but related only to the seriousness of their crimes: “If you’ve read the facts of these cases, you’ll know they were ugly, ugly.” He didn’t mind criticism if it was fair, but all too often, it was not. “Some allegations of ineffectiveness which are made in post-conviction cases are frivolous, simply not comporting with the facts and/or the law.”

Blaming trial defence counsel for death sentences, he pointed out, was merely a legal ploy: “Frankly, unless you’ve got fresh evidence, it’s the only way you can get relief, because you have to raise issues that haven’t been raised before. The question is, are you going to be bound by the facts, or make stuff up? You show me where I screwed up, and I’ll admit it.”

He acknowledged that he was a maverick, but he insisted that his methods were appropriate.

Professor Sean O’Brien of the University of Missouri law school, a veteran defence lawyer who has fought numerous capital trials and appeals – and who has known Duchardt for many years – disagreed. He believes Duchardt’s work has been so poor that it helps to explain a surprising fact: that federal courts in Missouri are far more likely to pass death sentences than those in any other state.

“Meeting the proper, nationally agreed standards of capital defence is demanding, and complying with them is expensive,” O’Brien said. “One reason why Missouri’s federal courts crank out so many death sentences is that they repeatedly appoint a lawyer – Duchardt – who has rejected these standards.”

Missouri has become a federal death penalty hotspot. Of the 62 prisoners on federal death row, nine were convicted in Missouri, 14.5% of the national total, though the state’s population of six million amounts to just 1.9% of the US as a whole. Since the 1990s, the chances of being sentenced to death in a federal court in Missouri have been many times higher than anywhere else.

To Duchardt, the explanation is simply that Missouri has more heinous murderers, more homicides with “egregious facts”. Again, O’Brien disagreed. “When the prosecution seeks the death penalty, it commits skilled lawyers with unlimited resources to get the job done. For an indigent defendant, getting a skilled lawyer who will demand the resources to make it a fair fight is like winning the lottery – you will probably live. Many defendants lose that lottery, and they get a lawyer more worried more about pleasing the court and the prosecutor than about fighting for the client. Those are the ones who die. When one lawyer produces nearly half the federal death sentences in a state, there’s a problem.”

Kansas City attorney Frederick Duchardt at the Clay County courthouse in Liberty, Missouri. Photograph: Christopher Smith/The Guardian

* * *

It has long been recognised that in state courts, the quality of capital defence lawyers is sometimes appalling. In Texas, which as of October 2016 had executed 538 men and women since 1982 – far more than any other state – at least three prisoners have been sentenced to death, despite the fact their attorneys spent parts of their trials asleep. At an appeal for one of them, prosecutors argued that this did not matter, because the man’s attorney only missed unimportant parts of the testimony. One Texas lawyer, Jerry Guerinot, has had 21 clients sentenced to death in state courts, including a British woman, Linda Carty. When I interviewed him in 2007, he said he was “an extremely aggressive lawyer” unlike those who “just sit in their chair and let the state run over them”. However, he admitted he spent barely an hour with her before her trial started, and failed to speak to crucial witnesses who would have supported her claim of innocence.

It is not easy to be a capital defence lawyer. By definition, most cases in which prosecutors seek the death penalty will be horrifying. Jurors will be questioned before they are sworn in, and those who admit they are opposed to capital punishment are excluded – creating an inherent, pro-death bias. The system is not always good at deciding which defendants really are the “worst of the worst”, and in 1994, Stephen Bright, founder of the Southern Centre for Human Rights in Atlanta, argued in a seminal paper that death sentences were generally imposed “not for the worst crimes, but the worst lawyers.”

African American people make up 12% of the population of the US, but almost half of federal death row’s inmates

By contrast, federal courts are supposed to be a paragon of American justice. Federal judges are appointed by the president, and prosecutors work for the Department of Justice in Washington. The US attorney general has to approve every federal case in which prosecutors seek the death penalty. As for the defence, public funding is generous: defence costs in a federal capital trial will usually be about $2m (in the Missouri state system, the average defence cost of a capital murder trial is $127,000).

Yet there is evidence that the federal death penalty is applied unevenly, disproportionately affecting minorities and the marginalised. African American people make up 12% of the population of the US, but almost half of federal death row’s inmates. Sinisterra was convicted of drug trafficking and murder, and sentenced to death under a law devised for drug trade “kingpins”, although, as a cartel courier and hitman, he was pretty low down the hierarchy.

Sinisterra’s main challenge against the death sentence – known in the trade as a “2255 motion”, after the relevant section of the US penal code – was handled by a team led by Tim Gabrielsen, a death penalty specialist from Arizona. When he started work in 2004, he formed the view that Duchardt’s conduct of the penalty phase of the trial ignored long-established practice. In many capital cases where prisoners’ lives have been spared, it is because their lawyers have been able to show that their childhoods were grotesquely abusive, that they were mentally ill, or intellectually disabled. In such circumstances, the US supreme court has set binding precedents, determining that prisoners who are not so much evil as deeply damaged should be shown mercy.

“Digging deep into the defendant’s background is at the core of mounting a defence: you have to persuade the jurors the defendant is not a monster, but a fellow human being,” said Professor O’Brien. “It isn’t enough to present testimony from mental health experts. You have to connect the jury with their life story. Some might say that’s touchy-feely. But it’s the way to save lives.”

For decades, the accepted way to get at this evidence has been to engage a “mitigation specialist”: an investigator skilled at persuading an offender’s friends and family to reveal painful secrets, and at finding the medical, psychiatric and other records that may support such disclosures. In 1998, America’s National Judicial Conference endorsed a report by a senior judge stating that all capital defence teams should include a mitigation specialist: this, it said, was nothing less than a “minimum standard of care”. The American Bar Association followed this with supposedly binding guidelines in 2003, saying lawyers “must” employ such experts.

However, when Duchardt was preparing for Sinisterra’s trial case, he chose not to do so. In advance of the appeal, Gabrielsen employed an experienced mitigation specialist of dual US-Colombian citizenship, who carried out a painstaking investigation in Colombia to see whether there was anything Duchardt had missed.

Talking to Sinisterra’s friends and family, the specialist discovered that from an early age, Sinisterra had been beaten by both his parents. His father used his fists, but sometimes his mother would lash him with a horsewhip, or submerge his head in a bucket of water.

When Sinisterra was seven, two men raped him at knifepoint, an attack so traumatic he ran away from home and lived on the streets. There, he was assaulted again. His attacker smashed his head against a lamppost so hard he was unconscious for two days. When he did finally go home, he was raped repeatedly by a friend of his mother who was a known paedophile, and by an elder brother who was high on drugs. While he was in his teens, two of his other brothers were murdered, one of them in front of him.

Gabrielsen also had Sinisterra assessed by a forensic neuropsychologist, Professor Antolin Llorente of the University of Maryland, who found that Sinisterra had an IQ of 68, below the threshold of what American law then called “mental retardation”. His head injuries had left him with permanent “organic brain damage”. This impaired his cognitive abilities, and he was unable to read or write.

It became clear that the view the original trial jury had of Sinisterra was far from complete. But almost as troubling as the details of his childhood were the reasons why Duchardt had failed to uncover them.

It turned out that Duchardt had left the preparation of the penalty phase to his junior co-counsel, Jennifer Herndon, who filed an affidavit describing her role for the appeal. In this she said that before the trial opened, she had also been getting ready for an unrelated capital case in St Louis, and was extremely busy. She said she had urged Duchardt to ask to have the trial postponed, to give them more time. He declined. She also said she had begged him to employ a mitigation specialist. In 10 years’ experience of capital trials, she said, she had never known a defence team without one.

Finally, just four weeks before the trial began, Herndon had travelled alone to Sinisterra’s home town, Buenaventura, and interviewed some of his family via an interpreter, but these were only “get acquainted” interviews, designed to establish “rapport and trust with the family”. They contained nothing revealing about his early life.

The ‘death chamber’ at the Texas Department of Criminal Justice Huntsville. As of October 2016, the state had executed 538 men and women since 1982. Photograph: Paul Buck/EPA

It is true, as Duchardt said, that it is common to claim “ineffective assistance of counsel” in challenges against sentence. Otherwise, a court will usually refuse to consider evidence that could have been heard at the trial. On the other hand, it is very hard to win such claims: the judge not only must be persuaded that the trial lawyer did a poor job, but that there is a “reasonable probability” that the unheard testimony would have produced a different outcome – a very high bar.

In April 1998, seven months before Sinisterra’s trial began, the supreme court reviewed a case with a direct bearing on his – the death sentence imposed on Terry Williams, a murderer tried in a state court in Virginia. Like Sinisterra, Williams had endured an appalling childhood, marked by frequent and extreme sexual and physical abuse, and had grave intellectual disabilities. None of this emerged until after he was sentenced.

The court decided that the mitigating evidence the jury never heard was compelling enough to save Williams’s life, and that his lawyer’s failure to produce it amounted to ineffective assistance. Had he cited this, and uncovered the evidence that made it relevant, this binding precedent should have been a great help to Duchardt’s defence. But he did not.

In 2002, the Supreme Court also issued a general ban on executing anyone who was “mentally retarded”, deeming this “the purposeless and needless imposition of pain and suffering”.

When I contacted Duchardt, he readily agreed to be interviewed, stipulating that we should meet in his favourite restaurant, Arthur Bryant’s Barbecue, in the Kansas City jazz district – a multiracial neighbourhood that once nurtured musicians such as Charlie Parker. Duchardt was proud of that heritage and proud of the restaurant, whose walls are decorated with photos of famous customers such as Jimmy Carter and Bill Clinton, Barack Obama, Steven Spielberg and Jack Nicholson. Duchardt insisted he would be paying, and after we met a second time in another traditional restaurant closer to his home, he told me to put my wallet away, saying I could pay when we met in England, which he hoped would be soon.

He hadn’t a bad word to say about anyone. The prosecutors he faced in court might be trying to kill his clients, but they were, he said, “in my experience, some of the best of the best of the local bar, who also take their duties to uphold the law very seriously. To call these folks worthy opponents against defence attorneys like me would be to say the least.”

Duchardt said that although the people he defended had committed horrifying crimes, “very few are any different to you or me. Some are among the nicest people I’ve met. It’s a classic case of ‘there but for the grace of God go I’. No matter what the facts of the case, most of us in the capital defence bar believe we should save every client’s life, and experience bitter, personal disappointment over a death penalty verdict.”

In the mid-1990s, Duchardt tried to prevent African-Americans charged with capital murder being tried by all-white juries in the Missouri state system. However, he admitted that when it came to death penalty defence, he had learned “on the job” – without any of the specialised training that has since become standard for “death-qualified” attorneys.

Fresh out of law school in 1980, he spent 15 years at the Missouri state public defender’s office. “Thirty years ago, none of that specialisation existed,” he said. “I was hired as an assistant public defender in the office in Clay County, a suburban portion of the Kansas City area. A year later, I was running that office.” Four years into his career, he successfully argued that a double murderer and rapist named William Wirth should not be executed. That led to his being appointed in a further five state capital trials.

Duchardt said he left the public defender system in 1995 after a row with a new boss. Since then, he has worked from his home in a Kansas City suburb as a sole practitioner. Most of the cases he has taken on in that time have been in the federal system, where fees are higher – although, as he pointed out, he was still making less than he would in commercial branches of the law.

Social work perspectives are accepted by well-educated, liberal people. But a lot of juries don’t have that education Frederick Duchardt

Here too he has had some success. His first federal capital client, Dennis Moore, was sentenced to life, as was the triple killer Demetrius Hargrove in 2005. Another, an alleged murderer and drug dealer named John P Street, was sentenced to death, but Duchardt managed to have his conviction overturned by challenging the forensic evidence. Duchardt appears to have been more successful with good old-fashioned forensics. His critics accept that in this instance, he did a good job. For the past 20 years, Duchardt said, he has defended “in most of the federal capital cases in the Western District of Missouri” – half the entire state.

Duchardt has no lack of confidence in his abilities. He was, he added, proud to be “old-school”, a term he used several times. He also said that his critics, with their faddish modern theories, knew much less than he did about how to impress juries – especially when it came to the penalty phase of trials. There, he said, he was proud to be a maverick. The American Bar Association could insist all it liked that capital defence teams must include a mitigation specialist, but in his view, they were usually of little value. “I do not follow orthodoxy,” he said. His voice became a sneer: such specialists focused on mere “social work type issues”, and he considered these irrelevant.

“As a lawyer, you have to understand your audience. Social work perspectives are accepted by a lot of well-educated, liberal people,” he said. “But there are a lot of people on juries who don’t have that education.” The problem with lawyers who tried to impose this approach was that they did not realise that often, it just didn’t work. “There’s a saying in American football: when your opponents can stop the plays, you need to find a new one.”

In the UK, it is axiomatic that a judge who has tried a case will never be appointed to hear its appeal. In America, however, one of the system’s peculiarities is that the judge who originally tried a capital case – and appointed the defence lawyer – will often be asked to decide whether that trial was fair. Few judges will relish admitting they got such matters of life and death wrong. Another peculiarity of the system is that in order to save his former client from execution, the lawyer must admit he made mistakes – which is something not many lawyers are keen to do.

Duchardt was appointed to all his federal capital cases by two judges, Gary Fenner and Fernando Gaitan. They were, he said, known for being tough, but “I’ve known both of them for years, and if you wanted to pick two guys to sit down and have a beer with, you’d pick those two. Fernando Gaitan has a dry sense of humour; Gary Fenner is just a very nice guy.”

Later, he amplified his comments in an email. “I believe both of those men are well-educated, well-experienced, and smart lawyers, and at the same time are very fine persons … whenever I have a case assigned to either of those two judges, I always rest assured that my client will get a fair hearing on the fact and the law.”

It was Fenner who presided over Sinisterra’s trial in 2000, and Fenner who dealt with his appeal. After the appeal lawyer Gabrielsen filed it, Duchardt set out an affidavit about his conduct of the trial, in which he insisted that he had always been “aware of all the information” about his client’s background, but had chosen not to use it for unspecified “strategic” reasons. He admitted that he had not known about Sinisterra’s cognitive disabilities.

In December 2007, Judge Fenner rejected the appeal, quoting extensively from Duchardt’s affidavit in his ruling. He concluded that far from providing ineffective assistance, the “strategic decisions of Mr Duchardt were well reasoned, as reflected by the record and the oversight of the court”.

But the case wasn’t over. Sinisterra appealed to the 8th circuit court of appeals, one of the 12 federal appeals courts, the last rung in the ladder below the US supreme court. This “remanded” it back to Judge Fenner, ordering him to conduct a hearing, in which the witnesses to Sinisterra’s childhood abuse gave evidence.

Duchardt also testified in person. Contradicting his earlier affidavit, he now admitted that before the trial, he had known nothing about the abuse Sinisterra had endured in childhood. But he blamed Herndon for this gap in his knowledge, saying he believed that when she went to Colombia, she would “exhaust all leads”. Gabrielsen commented: “He threw her under the bus.”

Sinisterra’s appeal lawyers were hopeful that after this hearing, the death sentence might be quashed. They never got a chance to find out. In March 2013, Sinisterra died from a heart attack in prison. Fenner had given no indication which way he was likely to rule, and the legal saga was over.

Gabrielsen still regards the case with bitterness. “Fred said in his affidavit that he knew all about Sinisterra’s background, and decided not to use it. Yet he didn’t even go to Colombia. And Judge Fenner simply believed everything Fred said.” As for Duchardt, he said he could not comment on the details of this or any of his cases beyond what was in the legal record.

* * *

In 1998, a 16-year-old named Jennifer Long, who lived on the Missouri side of Kansas City disappeared. All efforts to find her proved futile. The following year, while a habitual criminal named Wes Purkey was in a Kansas state jail awaiting trial for murdering an 80-year-old woman, he said that he had picked Long up in his car, kidnapped and murdered her. This was a crime that involved the crossing of the Kansas-Missouri state line, which bisects Kansas City. That meant that Purkey was tried in federal court. He explained the absence of Long’s body by saying that, having raped her and stabbed her to death, he had dismembered her remains and burned them in his fireplace.

Duchardt was appointed by Judge Gaitan to represent Purkey. To use Duchardt’s term, the facts of murder cases do not get much “uglier” than this. The prosecution decided to seek the death penalty, and it was clear that given Purkey’s confession, the best chance of saving his life would come during the second, penalty phase.

A mitigation specialist might have found plenty of material to make a case. Purkey, who was raised in Wichita, Kansas, had endured an almost unimaginably awful childhood. He was just six years old when his alcoholic mother began to abuse him sexually, the start of years of frequent, escalating abuse. On numerous occasions, Purkey witnessed his mother having sex with strangers. His father was also an alcoholic, and beat Purkey, telling him that only through violence could he show his worth as a man. Purkey was also seriously injured in a car crash, in which he suffered permanent brain damage.

Purkey’s lifelong friend Peggy Noe recalled in a later affidavit that when they were teenagers, he told her his mother was sexually abusing him. When she asked for details, “he would start stuttering really bad, to the point he couldn’t even talk”. Once Purkey brought Noe to his family home. It was afternoon, but “when we went in, his mother was in the bed in her nightgown, either drunk or hungover … Wes was ashamed of the abuse and ashamed that his home life was so horrible.” When they were in their 20s, they shared a motel room on a road trip, and she discovered he was still wetting his bed.

Purkey drifted into alcoholism and drugs, and spent time in prison: first for minor offences, and then, in 1980, for attempted murder. In 1987, by then 35, he was seen by a prison psychologist, Dr Rex Newton. Purkey asked him for therapy to deal with his childhood trauma and to help him turn his life around.

Newton, the prison psychologist, wrote that Purkey “displayed behaviours and characteristics common among many men in prison who started life being sexually abused by family members. The sexual abuse made Mr Purkey feel dirty and unworthy inside … those feelings turned to anger and rage in his adolescence when he became mature enough to understand how he was victimised.” He concluded: “Horrific things were done to Wesley Purkey throughout his childhood that sent him on a life path so filled with rage it practically guaranteed his ending up in prison.”

As he prepared for Purkey’s trial in November 2002, Duchardt decided once again not to employ a mitigation specialist. Instead, he relied on Mic Armstrong, a guilt-phase investigator and friend from his time with the state defender’s office. Duchardt told me that Armstrong, who died in 2015, was an “exceptional” investigator.

Duchardt did give the jury some information about Purkey’s childhood history of abuse. But he and Armstrong had failed to speak to Dr Rex Newton, so there was no corroboration. Without it, the prosecution was able to turn it against Purkey, thanks to testimony from Dr Park Dietz, a forensic psychologist. According to Dietz, Purkey’s claim to have endured physical and sexual abuse in childhood was a pack of lies, dreamed up to save him from lethal injection: the sort of thing criminals said when “facing capital murder charges and have people looking for bad things in childhood to help in mitigation”. The prosecutor called Purkey’s story the “abuse excuse”, claiming it was a “fairytale”.

Purkey was sentenced to death. It was only when his new legal team began to prepare his 2255 appeal, which was heard in 2008, that the evidence that might have produced a different outcome started to emerge. Purkey’s brother, Gary, had not only witnessed their mother’s abuse of Purkey, but had also been sexually assaulted by her on multiple occasions. His story, properly researched by a skilled mitigation specialist, might have done much to add credibility to Purkey’s own account. But the prospects of the jury hearing it had been sharply reduced by the fact that when Duchardt showed up at Gary’s house in order to interview him, he brought along his teenage son. This, Gary explained to Purkey’s appeal lawyers, made it impossible for him to make painful, personal disclosures.

Wes Purkey had a daughter, Angie: she could also have told the jury important things about her father and his dysfunctional background. She did take the stand at the trial, but examining her as a witness, Duchardt seemed to have had little idea of what she might say. The reason was that Duchardt and Armstrong had introduced themselves to Angie by arriving unannounced at her wedding, where, amid the celebrations, they sought to interview her about her father’s pending murder trial.

In 2003, the year after Purkey’s trial, a supreme court judgment overturned the death sentence imposed on convicted murderer Kevin Wiggins on the grounds he had been severely abused as a child. This case seemed to have considerable implications for Purkey’s appeal. In its judgment, the supreme court reiterated that the American Bar Association guidelines requiring mitigation specialists and the fullest possible investigation must be followed – and failure to do so would usually amount to ineffective assistance of counsel.

Duchardt knew about the Wiggins case when he came to submit an affidavit, justifying his conduct of Purkey’s trial, to Judge Gaitan. But in the course of an astonishing, self-justifying account that ran to 117 pages, he argued that this case had no relevance to Purkey and criticised his client’s appeals lawyers. “Despite the invective tone of the arguments advanced by counsel for Purkey, there is no factual or legal support for the arguments themselves,” he wrote.

Much of the affidavit consisted of detailed explanations as to why Duchardt had decided not to call particular witnesses, and it made assertions that had never been tested in court.

He admitted that he failed to tell the jury that Gary, like his brother, had been sexually abused by their mother, because he did not know about it. He claimed he had spoken to Dr Newton – although Newton said he had not.

Duchardt’s affidavit shocked the legal establishment. Purkey’s current lawyer, Rebecca Woodman, said: “He went way beyond what would have been acceptable, not only revealing confidential information, covered by attorney-client privilege, but actually accusing Purkey’s new counsel of lying.”

The appeals process presents the original defence lawyer with an awkward choice: admitting error might help save the client’s life, but at cost to the lawyer’s reputation. According to Professor Sean O’Brien of the University of Missouri law school, having once defended Purkey, Duchardt had “switched sides against his client”. O’Brien added: “The most troubling sections are when he claimed that witnesses weren’t called for ‘strategic’ reasons, even though those witnesses were never interviewed. You can’t possibly know what you have never bothered to learn. That’s not strategy, it’s a failure to prepare.”

“This argumentative response … did not seek to protect Purkey’s interests,” wrote Professor Tigran W Eldred in the Hofstra Law Review. “Rather, it was a full-throttled defence by Purkey’s trial lawyer of his own conduct.” In Eldred’s view, this was unethical. Lawyers had continuing obligations to their clients, especially those whose lives were at stake, and even if they were “motivated to protect their own self-interests”, they must not “rationalise their own misbehaviour”.

Judge Gaitan rejected Purkey’s appeal. Purkey appealed to the 8th circuit, and then the supreme court, again without success. He has now exhausted his appeals.

Duchardt’s next client to be sentenced to death was accused of a crime even more dreadful, if possible, than Purkey’s. The prosecution claimed that having met the heavily pregnant Bobbie Jo Stinnett in an online chatroom, Lisa Montgomery arranged to visit her in December 2004. Then, it was alleged, she strangled her, cut her unborn baby from her womb and took the infant home to care for her.

Duchardt was assigned to the case by Judge Fenner at the end of April 2006, but until the end of that year, he was getting ready for the imminent appeal and retrial of John P Street and was too busy to do much preparation, so he only visited Montgomery three times. Montgomery, it seemed, did not trust men, and in an effort to develop a rapport with her, Duchardt sent his wife, Ryland, to visit her in prison 16 times. Ryland had no experience of investigating death penalty cases. Her recent expertise was in horse therapy for autistic children.

As the trial date approached in October 2007, Duchardt was focused on the guilt phase, convinced he could secure a not-guilty verdict through two contradictory strategies. The first was to suggest that Stinnett was killed not by Montgomery but by Montgomery’s brother, Tommy, who had then given his sister the baby. But shortly before the trial it emerged that Tommy had an alibi: at the time of the murder, he had been with his probation officer.

Lisa Montgomery was sentenced to death for murdering Bobbie Jo Stinnett and then stealing her unborn baby. Photograph: AP

Duchardt was forced to abandon this line of defence just a week before the trial began, and it had a disastrous consequence. The rest of Montgomery’s family, who might have been able to give the “life story” mitigation evidence that could save her from death row, believing she had tried to blame her brother, withdrew their cooperation. Duchardt’s second strategy was to admit that although Montgomery was the killer, she was not guilty by reason of insanity – because, he believed, she had been suffering from a phantom pregnancy, or pseudocyesis.

The pseudocyesis theory did not stand up. Before the trial started, the prosecution managed to have the diagnosis offered by Duchardt’s main expert excluded from the case altogether, on the grounds it had no scientific basis. Lisa Montgomery was convicted of murder and sentenced to death. Her appeals team, led by Kelley Henry from an office in Nashville, dug deep into her background, swiftly learning there were very good reasons why she did not trust men. Of all Duchardt’s clients, the physical and sexual abuse she had suffered as a child and young woman was the most extreme and relentless.

The house in Missouri where Bobbie Jo Stinnett was murdered. Photograph: Larry W. Smith/Getty Images

Her stepfather raped her over many years. When she turned 13, he built a special room in his trailer where he could attack her in privacy. He also stored liquor there, which she would drink in order to block out her horrifying reality. The following year, her mother burst in as she was being attacked. There followed what her appeal filing describes as “the most terrifying night of her life”, as her mother held a gun against her daughter’s head.

Montgomery tried to escape her chaotic home by marrying when she was just 18. The couple had four children. But both this and a subsequent marriage were marked by further violence and abuse. The experts who examined Montgomery post-conviction found that unknown to her trial jury, her upbringing had left her suffering from florid psychosis, bipolar disorder and post-traumatic stress disorder. She was often disassociated from reality, and as a result of her many beatings, had suffered permanent brain damage.

But before her trial, neither the prosecution nor the defence had investigated the relationship between Montgomery’s many symptoms and her appalling history. She had seemed to the jury impassive and unemotional, as if she bore no remorse. In fact, this was the result of powerful antipsychotic medication. About the only relevant condition she had not suffered from was pseudocyesis. The evidence that Lisa Montgomery was a victim as much as a perpetrator should have been overwhelming.

Just as he had in the Purkey case, Duchardt responded to Montgomery’s appeal with an affidavit of more than 100 pages defending his conduct, insisting that “none of the issues raised” by her appeal lawyers “has merit”. He added: “I have tried and prepared more than a dozen capital cases, and I have addressed complex mental health issues in many … My guess is that my credentials stack up as well as any capital case attorney or ‘mitigation specialist’ to be found. I know that my credentials are as good or better than those who have been relied upon as experts by Current Counsel for Ms Montgomery.”

In fact, Duchardt concluded, his former client’s appeal lawyers were nothing more than “spoiled, selfish prima donnas”. This time, Judge Fenner did not accept Duchardt’s word, but held a hearing. Duchardt testified over two days in November 2016. On the first, he sported a Kansas City Chiefs football team tie. On the second, he replaced it with one bearing the stars and stripes.

With the prosecutors, his demeanour was friendly: he even inquired after the health of the “lovely wife” of the lawyer cross-examining him. His attitude while being questioned by Montgomery’s appellate defence was more hostile. Repeatedly, he interrupted one of her lawyers, Amy Harwell, telling her patronisingly there was a “problem with the way you’re asking the questions, Ms Harwell”.

When it was put to him that he “didn’t like mitigation specialists”, he denied this, saying: “I don’t know where this comes from.” He refused to accept that pursuing the pseudocyesis line had been an error. As for the evidence of Montgomery’s appalling background, in Duchardt’s view, much of the research into this by other lawyers was “garbage”.

It was clear that Duchardt was not going to admit he had made mistakes, even though it would have helped his former client if he did so. Montgomery’s defence lawyers declined to comment for this article. Fenner’s decision whether to quash her sentence is expected by the end of the year.

According to Professor O’Brien, by defending himself so fiercely, once again, Duchardt seems to be trying to impress the judges who appoint him. But, he added: “The court is not the client.”

The election of Donald Trump has set the clock ticking. The Obama administration has not sought to execute anyone on federal death row, although there are several inmates who have exhausted their appeals. Trump has been an outspoken supporter of capital punishment for 30 years, as is Jeff Sessions, whom Trump has announced he will nominate as US attorney general. “Death penalty, it’s going to happen,” Trump said in one campaign speech. “I expect use of the death penalty to be ramped up really quickly,” said Rebecca Woodman. “Defending capital clients is going to be much harder.”

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