The Devil in the Details
It took nearly two decades before Theodore John Kaczynski was identified as the man responsible for the "Unabom" explosions that were sent through the mail to selected targets. His attacks followed an erratic pattern, so it was difficult for investigators to pin him down until after he'd already killed three people and injured twenty-nine.
His bombs were made by hand. The first one in 1978 was found in a parking lot at the University of Illinois in Chicago and was "returned" to a professor at Northwestern University. A security guard was injured. Within a year, there were three more bombs, but the first actual fatality occurred in 1985 when a computer storeowner opened the dangerous package. That same year, the "Junkyard Bomber" had sent a written communication to the San Francisco Examiner. He identified himself as "FC," a terrorist who belonged to a group called the Freedom Club, and they were taking a stand against technology and science. The initials F. C. were then used on the bombs and in future communications.
In 1987 the mystery bomber was spotted. He was white, about six feet tall, middle-aged, and had reddish-blond hair. However, he wore sunglasses and a sweatshirt, so he remained somewhat disguised. No one caught him.
Then six years went by, and in 1994, one of the terrorist bombs decapitated a New Jersey advertising executive. It had all the earmarks of the "FC" terrorist. The third death took place the following year in California, when the sixteenth bomb killed Gilbert Murray. Two months later, a 35,000-word manifesto arrived at the offices of several major newspapers, sent by someone who identified himself as the person whom the FBI called "the Unabom." Only if his manuscript were printed in full, he insisted, would the bombings cease. The papers printed it and there were no more bombs, but this person sent several more letters to targeted individuals. After that, the FBI closed in on him.
On April 3rd, 1996, Kaczynski was arrested in his isolated cabin in Montana. His own brother David, tipped off by his wife after she'd read the manifesto, had noticed similarities between it and things he heard from Ted, so he brought this to the attention of officials. They hired a textual analyst, James Fitzgerald, to help them to make the connection so they could get a search warrant. Inside Kaczynki's cabin they found an abundance of writings that matched the sentiments of the Unabomber, along with materials for making bombs.
In his book, Author Unknown: On the Trail of Anonymous, Vassar literature professor Don Foster has brought the details of that pivotal analysis to light. Although he himself made no contribution to the FBI's identification of the serial bomber, he was instrumentally involved in the court case. That places him in a prime position to explain the use of linguistic analysis as a forensic tool.
Working with anonymous documents and relying on the fact that no two people use language in exactly the same way, Foster uses what he refers to as attributional analysis to try to identify the author of a specific record. This method has been in development in the linguistic community for over two centuries, and has a solid evidential basis.
"The scientific analysis of a text," Foster writes, "can reveal features as sharp and telling as anything this side of fingerprints and DNA." The pattern of unique differences in each person's use of language, along with repetition of those traits throughout his or her writing, provide the internal evidence that links a person to the piece of writing under examination. "Human beings are prisoners of their own language," says Foster.
This technique is not about handwriting analysis, but focuses on linguistic content, and is undertaken by linguistic experts all over the country. Yet Foster has stood out ever since he put himself on the line publicly with a controversial discovery: He earned his initial fame when he identified an obscure funeral poem as having been written by William Shakespeare. By comparing the piece by "W. S." with what he knew from his Shakespeare scholarship, he made a painstakingly convincing case. It wasn't long before his announcement about that breakthrough got him involved in a more contemporary mystery: Foster was invited to try to unmask the anonymous author of the political novel Primary Colors. He did so within a week, correctly naming Joe Klein. The accuracy of his work made him fair game for attorneys seeking an expert witness, and that's how he got involved in the Unabomber case.
But first, just exactly what does he do?
He describes the general method as follows: When asked, "Who wrote this document?" Foster searches text databases that may contain similar language habits. "The language used by an unknown author," Foster says, "can often help establish the writer's age, gender, ethnicity, level of education, professional training, and ideology. Linguistic clues typically include such evidence as vocabulary word-usage, slang, professional jargon, regionalisms spelling, grammar, syntax and even such matters as punctuation. Other kinds of textual evidence may include borrowed or influential source material, document formatting, and the physical document itself, such as the watermarked paper or canceled postage."
Initially Foster was invited to join Kaczynski's defense team because they needed expert assistance in damaging the credibility of the text analysis made by James Fitzgerald for the FBI. Fitzgerald had catalogued similarities between known writing samples of Kaczynski with the Unabomber's writing, which had established probable cause for a search warrant for Kaczynski's cabin. The defense wanted to show that his attributional work was flawed, which undermined the warrant, and that meant that all evidence seized could be thrown out.
Foster studied the FBI affidavit, along with some of the writing samples, and concluded that it was likely that Kaczynski was the Unabomber, so he declined to assist the defense. Then he heard from the prosecution team. They wanted him on their side, to shore up Fitzgerald's work against the linguist that the defense had managed to recruit.
Foster agreed to help, and began to examine a pile of documents written by Kaczynski from letters to short stories to dream narratives and then read some of the sources that had inspired Kaczynski's ideas and manner of communication. Foster's task was to give his expert opinion on whether the FBI affidavit was reasonable, and whether the FBI had accurately represented the attributional evidence. The defense had argued that the manifesto could have been written by practically anyone with a grudge against modern technology. They also pointed out that words often misspelled by Kaczynski had been spelled correctly in the manifesto, and that while Kaczynski tended to split infinitives, only a single instance of a split infinitive appeared in the manifesto.
In his report, Foster described how individualized a person's writing really is specifically Kaczynki's and then showed that the problems pointed out by the defense were not really indicative of the writings of two different people; they had to be understood in context. Based partly on this, the judge denied the defense's motion to suppress, and this became a benchmark decision on the legitimacy of attributional analysis for the legal procedure.
Foster then took it a step further for the future of forensic investigation by asking the question whether "FC" could have been identified merely from the manifesto and his other written documents and known behaviors. "I came to believe," he writes, "that the authorities could have been led to Ted Kaczynski without fingerprints, without DNA, without eyewitnesses, without the forensic analysis of bomb components...just by paying extraordinarily close attention to the bomber's own words."
He goes on to describe what document analysis can contribute to a criminal profile, specifically citing the methods he used in this case. Indicating that nothing is irrelevant not even the stamp used to mail things Foster claims that a reading of FC's letters and his manuscript points to:
- a man much older than the FBI profilers thought because he was influenced by New York's Mad Bomber from the 1950s
- a man highly educated
- he read texts or novels popular in the 60s, such as Brave New World and certain sociological treatises
- he was preoccupied with Eugene O'Neill, a known anarchist
- he used the sinking of the Titanic as a metaphor for society's blindness and as a way to target his victims and get a message across
- he tended to take ideas even mimic styles from the writings of others
- he searched for victims in specific academic reference works
- his favorite magazines were Scientific American and The Saturday Review
- he was strongly influenced by the writings of Joseph Conrad
- he identified himself with wood
- he disliked modern technological progress
- his favorite research haunts were libraries in northern California.
In the end, by zeroing in on an offender's sources of information the books, magazines, reference works, and primary intellectual influences something can be inferred about his physical whereabouts. In Kaczynski's case, he had even written a letter to the editor of The Saturday Review using language that bore strong similarities to the way in which he later wrote the manifesto. That letter bore his name and hometown.
It's not the first case to rely on linguistic analysis, but it may be the case that brought the method most fully into public awareness. It also made the FBI increasingly more aware of its value for criminal investigations. In fact, as Foster points out, there are numerous possibilities for is application.
"When confronted with an anonymous threat to shoot the President, or to bomb an abortion clinic, or to blow an airliner out of the sky," he says, "the FBI must assess the threat and identify the author before it's too late. When a terrorist attack does occur, various unrelated organizations may claim responsibility for the offense, seeking only free publicity for their cause yet one or more of those statements may, indeed, be useful in solving the crime. Following a homicide, police or the media may receive anonymous tips information sent, possibly, by a credible witness or by the actual offender, or else by a mischief-maker or well-intentioned psychic; such documents may be accurate, merely speculative, or deliberately misleading."
With the rise of the Internet, anonymous communications for unlawful purposes is a growing problem, especially in terms of the time and resources wasted on investigations of hoaxes. "Private persons as well as celebrities and politicians may be libeled, harassed, or threatened by anonymous writers. A disgruntled worker may circulate anonymous attacks on his employer. The owner of a small business may distribute unsigned letters to trade unions, clients, newspapers, or government agencies that are damaging to a competitor. Stocks can be manipulated by postings to the Internet or by anonymous tips to major stock funds. Wills, historical documents, and literary manuscripts may be forged. In short, the malicious and criminal uses of anonymity are boundless and many of those persons who engage in such activity are habitual offenders."
While textual analysis has proven its worth and will continue to play a part in forensics, another linguistic method that purports to take things much more deeply claims to be able to solve crimes, too. In fact, it was offered as a way to finally solve the murder of JonBenet Ramsey.