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From his prison cell, Ted Kaczynski — the “Unabomber,” who terrified the nation in the 1980s and early 1990s — has carried on a remarkable correspondence with thousands of people all over the world. As the 20th anniversary of his arrest approaches, Yahoo News is publishing a series of articles based on his letters and other writings, housed in an archive at the University of Michigan. They shed unprecedented light on the mind of Kaczynski — genius, madman and murderer.

Long before she became a headline name for her efforts to save Boston Marathon bomber Dzhokhar Tsarnaev from the death penalty, lawyer Judy Clarke had another, equally notorious client: Ted Kaczynski, the Unabomber. And her strategy in both cases was similar: Faced with overwhelming evidence that they were guilty of horrific crimes, she searched for details and insights into their lives that might lead jurors to see them as just human enough to spare them from death.

To do that with Kaczynski, though, she felt she had to understand his motivation for the string of terror bombings that left three people dead and more than a score injured, and narrowly missed bringing down an airliner. In late 1996, awaiting trial in Sacramento, Calif., Kaczynski took out a pencil and a yellow notepad and began a letter to Clarke:

“Judy … You asked how someone like me, who seems to be sensitive to other people’s feelings and not vicious or predatory, could do what I’ve done,” he wrote in the letter he labeled “VERY SENSITIVE.” “Probably the biggest reason why you find my actions incomprehensible is that you have never experienced sufficiently intense anger and frustration over a long enough period of time. You don’t know what it means to be under an immense burden of frustrated anger or how vicious it can make one.”

For Kaczynski, there was “no inconsistency between viciousness” toward the people he considered responsible for his anger and “gentleness” toward others, he wrote. In fact, he argued, “having enemies augments one’s kindly feelings toward those whom one regards as friends or as fellow victims.”

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But — in an admission he appears never to have made to anyone else — Kaczynski allowed that he did sometimes feel conflicted about what he’d done. Were his deadly bombs justified? “A qualified yes,” he told Clarke — depending on his mood at the time and whether he felt his campaign against the dehumanizing effects of modern technology was “winning or losing.”

The previous fall, Kaczynski had achieved what he considered a significant victory. Under the threat of continued violence, the New York Times and Washington Post published the 35,000-word anti-technology manifesto that had been his life’s work. (The appearance of the manifesto led to his eventual arrest, when his brother, David, recognized that the Unabomber’s language and ideas echoed letters he had received from his brother years earlier.) But, as Kaczynski told Clarke, he didn’t feel the satisfaction he’d hoped for. “When I feel that I’m winning … I start feeling sorry for my adversaries, and then I have mixed emotions about what I’ve done,” he wrote.

The Washington Post's Sept. 19, 1995, issue containing the Unabomber's manifesto. At the request of Attorney General Janet Reno and the FBI, the Post published the unedited 35,000-word manifesto of the Unabomber, Ted Kaczynski, in hopes of ending his 17-year letter bomb campaign. (Photo: Evan Agostini/Liaison via Getty Images)

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The letter is a measure of how much Kaczynski had come to like and trust Clarke. Although he would eventually enter a guilty plea at the start of his trial in 1998, receiving eight consecutive life sentences, he refused for years to admit or explain his actions to anyone else. In his letter, he wrote he did not expect her to agree that the crimes he committed as the Unabomber were justified, but he wanted to offer an explanation anyway. “I can’t blame you for feeling troubled about what I’ve done,” Kaczynski wrote to Clarke. “In fact, I respect you the more because you have raised this difficult question, even though it makes me uncomfortable to try to answer it.”

The Unabomber was only the second high-profile case of Clarke’s career. (The first was Susan Smith, the South Carolina mother who was accused of intentionally drowning her two young sons.) Kaczynski’s papers, comprising 90 boxes in an archive at the University of Michigan, offer some insight into how the famed defense attorney, who famously refuses to speak to reporters (and did not respond to comment for this story), does her job.

Appointed to the case in the summer of 1996, a few months after Kaczynski had been arrested at his remote cabin in Montana, Clarke soon became one of Kaczynski’s favorite people. In letters to others, the bomber almost moons over her, writing of how interesting she is and how much he enjoys spending time with her. It seems clear that he adored Clarke and probably had a crush on her. For Kaczynski, who never had a girlfriend — a source of despair in his diaries — Clarke, who was and is married, was his first significant female relationship.

While news stories have long suggested Kaczynski was hostile to his attorneys from the outset, his letters show the opposite is true. He actually bonded with most of his legal team, whom he came to regard as close, personal friends. After more than 20 years of living as a recluse, Kaczynski was now spending hours every week with lawyers and defense investigators who visited him in jail as often as they could, trying to keep up his spirits. They gave him work to keep him busy, including going through the many coded writings that had been found in his cabin. For Christmas, they gave him a dictionary — ­­­which Kaczynski treasured.

“We developed a unique relationship with him,” recalled Quin Denvir, a former federal public defender who was Clarke’s co-counsel on the case. “We spent hours with him, trying to draw him out, especially Judy.”

What Kaczynski did not know — and what would ultimately sour the relationship — was that his attorneys were preparing to mount an insanity defense. With such overwhelming evidence of guilt, it was the only thing they believed might save him from the death penalty. Though court records show that the defense had been laying the groundwork for months, the bomber apparently did not realize what was happening until late 1997 — just weeks before his trial was to begin. While he was angry with his entire defense team, Kaczynski focused most of his wrath on Clarke.

Unabomber Letters

In a blistering letter from that time, addressed to his lawyers, “(and most of all) Judy,” Kaczynski rages that his legal team exploited “a lonely man’s hunger for friendship in order to manipulate and deceive him” over the use of a mental health defense and that he regarded that betrayal as “many times worse than my brother’s .”

“They have professed warm friendship for me, they have actively cultivated my friendship so that I developed a strong affection for most of them,” he wrote. “Some of them I even loved.”

Though court psychiatrists had diagnosed him as a schizophrenic, Kaczynski rejected the analysis and the idea of the mental health profession at all. He was concerned it would undermine the ideology he had laid out in the Unabomber manifesto. “Of all the things you could have done to me, what you have done is the cruelest,” he wrote. “I would rather be killed, crucified, blinded — anything but this.”

Kaczynski seemed particularly hurt that Clarke had decided “from the outset” that he was mentally ill. He was angry and upset that she apparently hadn’t believed him when he told her that his parents had verbally and emotionally abused him when he was a child. And he was angry that she was using an insanity defense to save him from the death penalty — which he wanted because he couldn’t bear the idea of spending the rest of his life behind bars.

Even as he raged against his lawyers and asked the judge to fire them or to allow him to represent himself, Kaczynski felt guilty, especially about Clarke. “In spite of all this, I find her personality so attractive that I think I enjoy talking with her more than any other person I have ever known, and I have a strong sense of rapport with her,” he wrote in a January 1998 letter.

But, he wondered, “Is she a friend or an enemy? In practical terms, she is an enemy of me and of everything I stand for, but in terms of personal relations, she is very friendly toward me, and I have warm feelings of friendship toward her.”

Members of Unabomber Ted Kaczynski’s defense team, from left, attorneys Quin Denvir and Judy Clarke, jury consultant Denise de La Rue and attorney Gary Sowards, walk to the federal courthouse in Sacramento, Calif., on Dec. 9, 1997. (Photo: Rich Pedroncelli/AP)

In late January, as the trial was beginning, Kaczynski attempted to fire his legal team and represent himself. The judge blocked it, but the upshot was a deal in which Kaczynski agreed to plead guilty in exchange for eight life sentences without parole. Even as he did so, the bomber raged at his attorneys — and especially Clarke — for reinforcing “the public’s perception of me as a madman.”

Still, Kaczynski, even after his sentencing, continued for many years to exchange correspondence with Clarke, Denvir and other members of his legal team. He sent holiday cards to Clarke, who sent him postcards from her vacations and a photo of her pug, Jax.

But as Clarke became busy with other cases, the correspondence dropped off and Kaczynski once again became bitter toward her. (Her last letter on file in the archive is from 2002.) When a pen pal wrote of his plans to visit Asheville, N.C., Kaczynski made a snide comment, noting that he’d heard the city was nice — except for its being the hometown of his former attorney, Clarke.

In fall 2013, journalist Mark Bowden contacted Kaczynski for a profile he was writing of Clarke, tied to her defense of the Boston Marathon bomber. “I’ll give you my general impression: Judy Clarke is a bitch on wheels and a real sicko,” Kaczynski wrote back, according to a letter in his archive. The months that Clarke and her team spent trying to understand him made no difference to his fate: Life without parole was probably the best outcome he could have achieved at trial, and he got there just by taking a plea. He is serving it at the federal “supermax” in Florence, Colo., where his fellow inmates include some of Clarke’s other notorious clients, including Atlanta Olympics bomber Eric Rudolph; Zacarias Moussaoui, who was implicated in the 9/11 attacks — and Tsarnaev, who was sent there after his conviction and sentencing last year. Despite Clarke’s efforts, he was sentenced to death, the only one of her clients she couldn’t save.

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