Because of the material used to make the mail bombs,
U.S. postal inspectors, who initially had responsibility for the case, labeled the suspect the "Junkyard Bomber". FBI Inspector Terry D. Turchie was appointed to run the UNABOM (University and Airline Bombing) investigation. In 1979, an FBI-led
task force that included 125 agents from the FBI, the
Bureau of Alcohol, Tobacco and Firearms (ATF), and the U.S. Postal Inspection Service was formed. In 1980, chief agent
John Douglas, working with agents in the FBI's
Behavioral Sciences Unit, issued a psychological
profile of the unidentified bomber. It described the offender as a man with above-average intelligence and connections to academia. This profile was later refined to characterize the offender as a
neo-Luddite holding an academic degree in the
hard sciences, but this psychologically based profile was discarded in 1983. FBI analysts developed an alternative theory that concentrated on the physical evidence in recovered bomb fragments. In this rival profile, the suspect was characterized as a
blue-collar airplane mechanic. The UNABOM Task Force set up a
toll-free telephone hotline to take calls related to the investigation, with a $1 million (equivalent to approximately $ million in ) reward for anyone who could provide information leading to the Unabomber's capture. Before the publication of
Industrial Society and Its Future, Kaczynski's brother, David, was encouraged by his wife to follow up on suspicions that Ted was the Unabomber. David was dismissive at first, but he took the likelihood more seriously after reading the manifesto a week after it was published in September 1995. He searched through old family papers and found letters dating to the 1970s that Ted had sent to newspapers to protest the abuses of technology using phrasing similar to that in the manifesto. Before the manifesto's publication, the FBI held many press conferences asking the public to help identify the Unabomber. They were convinced that the bomber was from the Chicago area where he began his bombings, had worked in or had some connection to Salt Lake City, and by the 1990s had some association with the
San Francisco Bay Area. This geographical information and the wording in excerpts from the manifesto that were released before the entire text of the manifesto was published persuaded David's wife to urge him to read it.
After publication After the manifesto was published, the FBI received thousands of tips. David later hired Washington, D.C. attorney Tony Bisceglie to organize the evidence acquired by Swanson and contact the FBI, given the presumed difficulty of attracting the FBI's attention. Kaczynski's family wanted to protect him from the danger of an FBI raid, such as those at
Ruby Ridge or
Waco, since they feared a violent outcome from any attempt by the FBI to contact Kaczynski. In early 1996, an investigator working with Bisceglie contacted former FBI hostage negotiator and criminal profiler Clinton R. Van Zandt. Bisceglie asked him to compare the manifesto to typewritten copies of handwritten letters David had received from his brother. Van Zandt's initial analysis determined that there was better than a 60 percent chance that the same person had written the manifesto, which had been in public circulation for half a year. Van Zandt's second analytical team determined a higher likelihood. He recommended Bisceglie's client contact the FBI immediately. recognized similarities in the writings using
linguistic analysis and determined that the author of the essays and the manifesto was almost certainly the same person. Combined with facts gleaned from the bombings and Kaczynski's life, the analysis provided the basis for an affidavit signed by Terry Turchie, the head of the entire investigation, in support of the application for a
search warrant. David had once admired and emulated his older brother but had since left the
survivalist lifestyle behind. He had received assurances from the FBI that he would remain anonymous and that his brother would not learn who had turned him in, but his identity was leaked to
CBS News in early April 1996. CBS anchorman
Dan Rather called FBI director Louis Freeh, who requested 24 hours before CBS broke the story on the
evening news. The FBI scrambled to finish the search warrant and have it issued by a federal judge in Montana; afterward, the FBI conducted an internal leak investigation, but the source of the leak was never identified. They also found what appeared to be the original typed manuscript of
Industrial Society and Its Future. By this point, the Unabomber had been the target of the most expensive investigation in FBI history at the time. A 2000 report by the United States Commission on the Advancement of Federal Law Enforcement stated that the task force had spent over $50 million (equivalent to approximately $ million in ) on the investigation. After his capture, theories emerged naming Kaczynski as the
Zodiac Killer, who murdered five people in
Northern California from 1968 to 1969. Among the links that raised suspicion were that Kaczynski lived in the San Francisco Bay Area from 1967 to 1969, that both individuals were highly intelligent with an interest in bombs and codes, and that both wrote letters to newspapers demanding the publication of their works with the threat of continued violence if the demand was not met. Kaczynski's whereabouts could not be verified for all of the killings. Since the gun and knife murders committed by the Zodiac Killer differed from Kaczynski's bombings, authorities did not pursue him as a suspect. Robert Graysmith, author of the 1986 book
Zodiac, said the similarities are "fascinating" but purely coincidental. At one point in 1993, investigators sought someone whose first name was "Nathan" because the name was imprinted on the envelope of a letter sent to the media.
Diary and cipher Theodore Kaczynski maintained extensive personal journals spanning more than 25 years, from approximately 1969 until his arrest in 1996. These journals, totaling over 40,000 handwritten pages, documented his daily life, philosophical beliefs,
emotional state, and detailed accounts of his
criminal activities, including bomb-making experiments and the Unabomber attacks. Some entries were written in plain text, while others were encrypted using two custom
cipher systems Kaczynski developed to conceal sensitive information. The journals were discovered during the
FBI raid on his Montana cabin on April 3, 1996. In enciphered entries, he detailed his bombings, expressing frustration over non-lethal outcomes and satisfaction when devices caused fatalities. He numbered his bomb-making experiments, such as "Experiment 97" which killed Hugh Scrutton in 1985, and "Experiment 244" which killed Thomas Mosser in 1994, noting technical details like chemical mixtures, weights, and modifications to enhance lethality. Code #I, the more complex system, was documented in "Notebook X" and involved a 54x42 grid matrix to generate a long key sequence through four reading phases (horizontal, vertical, diagonal). FBI
cryptanalyst Michael Birch decoded the journals, which served as key evidence in the case. Kaczynski's lawyers, headed by Montana
federal public defenders Michael Donahoe and
Judy Clarke, attempted to enter an
insanity defense to avoid the death penalty, but Kaczynski rejected this strategy. On January 8, 1998, he asked to dismiss his lawyers and hire
Tony Serra as his counsel; Serra had agreed not to use an insanity defense and instead promised to base a defense on Kaczynski's anti-technology views. After this request was unsuccessful, Kaczynski tried to kill himself on January 9. Sally Johnson, the psychiatrist who examined Kaczynski, concluded that he suffered from "
paranoid"
schizophrenia, though the validity of this diagnosis has been criticized. In his 2010 book
Technological Slavery, Kaczynski said that two prison psychologists who visited him frequently for four years told him they saw no indication that he suffered from paranoid schizophrenia and the diagnosis was "ridiculous" and a "political diagnosis". Some contemporary authors suggest that people (notably Kaczynski's brother and mother) purposely spread the image of Kaczynski as
mentally ill intending to save his life. On January 21, 1998, Kaczynski was declared competent to stand trial by federal prison psychiatrist Johnson "despite the psychiatric diagnoses" and prosecutors sought the death penalty. Kaczynski pleaded guilty to all charges on January 22, 1998, accepting
life imprisonment without the possibility of parole. He later tried to withdraw this plea, claiming the judge had coerced him, but Judge
Garland Ellis Burrell Jr. denied his request and the
United States Court of Appeals for the Ninth Circuit upheld that denial. In 2006, Burrell ordered that items from Kaczynski's cabin be sold at a "reasonably advertised Internet auction". Items considered to be bomb-making materials, such as diagrams and "recipes" for bombs, were excluded. The net proceeds went toward the $15 million (equivalent to approximately $ million in ) in restitution Burrell had awarded Kaczynski's victims. Kaczynski's correspondence and other personal papers were also auctioned. Burrell ordered the removal, before sale, of references in those documents to Kaczynski's victims; Kaczynski unsuccessfully challenged those redactions as a violation of his freedom of speech. The auction ran for two weeks in 2011, and raised over $232,000 (equivalent to approximately $ in ). Following Kaczynski's sentencing to life without parole, he gifted his cabin to
Scharlette Holdman, an anti-death penalty activist and mitigation specialist who played a role in preventing him from receiving the death penalty. The U.S. government refused to allow Holdman to keep the shack. == Incarceration and death ==