Cryptanalysts problem (or FBI has a hard time)

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Cryptanalysts problem (or FBI has a hard time)

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The letter from a gang member in prison to a friend on the outside seemed normal enough. “Saludos loved one,” it began, and went on to describe the perils of drug use and the inmate’s upcoming visit from his children.
But closer inspection by examiners in our Cryptanalysis and Racketeering Records Unit (CRRU) revealed that this seemingly ordinary letter was encoded with a much more sinister message: every fifth word contained the letter’s true intent, which was to green-light the murder of a fellow gang member.


A bomber's enciphered instructions for making ricin poison.
Gallery: More Codes
Breaking such codes is CRRU’s unique specialty. Despite the FBI’s extensive use of state-of-the-art computer technology to gather intelligence, examine evidence, and help solve crimes, the need to manually break “pen and paper” codes remains a valuable—and necessary—weapon in the Bureau’s investigative arsenal.
That’s because criminals who use cryptography—codes, ciphers, and concealed messages—are more numerous than one might expect. Terrorists, gang members, inmates, drug dealers, violent lone offenders, and organized crime groups involved in gambling and prostitution use letters, numbers, symbols, and even invisible ink to encode messages in an attempt to hide illegal activity.

Breaker, Breaker
Breaking any code involves
four basic steps:
1. Determining the language used;
2. Determining the system used;
3. Reconstructing the key; and
4. Reconstructing the plaintext.
Consider this cipher: Nffu nf bu uif qbsl bu oppo.
Now apply the four steps:

1. Determining the language allows you to compare the cipher text to the suspected language. Our cryptanalysts usually start with English.

2. Determining the system: Is this cipher using rearranged words, replaced words, or perhaps letter substitution? In this case, it’s letter substitution.

3. Reconstructing the key: This step answers the question of how the code maker changed the letters. In our example, every character shifted one letter to the right in the alphabet.

4. Reconstructing the plaintext: By applying the key from the previous step, you now have a solution: Meet me at the park at noon.
Bookies, pimps, and drug traffickers, for example, all keep records of their dealings, explained Dan Olson, chief of CRRU, which is part of the FBI Laboratory. “If there is money and credit involved in a transaction,” Olson said, “there has to be an accounting of that at every step of the way, even if it’s on a match pack, hotel stationary, or the back of a cocktail napkin.”
The unit’s forensic examiners are often tasked with decoding encrypted evidence after subjects have been arrested. But CRRU also plays an important role in thwarting crime by intercepting coded messages—like the prison letter above—particularly among inmates and gang members. “We solve crimes,” Olson said, “but we actually prevent more crimes than we solve.”
The art of breaking codes is an “old-fashioned battle of the minds” between code makers and code breakers, Olson added, explaining that CRRU is the only law enforcement unit anywhere that deals exclusively with manual—as opposed to digital—code breaking.
“We would love to find our counterparts somewhere in the world,” he said, “but so far we haven’t been able to. No one seems to have the niche that we have.”
Becoming a cryptanalyst requires a basic four-month training course and plenty of continuing education to learn the age-old patterns and techniques of code makers. Olson insists that almost anyone can learn basic code-breaking skills (see sidebar), but certain personality types seem best suited to the job, including those who like solving puzzles and who are determined and tenacious.
The unit’s examiners include linguists, mathematicians, and former law enforcement officers like Debra O’Donnell, who worked drug and gang cases in New Jersey before joining the Bureau. “This is very rewarding work,” O’Donnell said, “but you have to have the right temperament for it, because you can’t break every code.”
Still, since World War II, when Bureau cryptanalysts were responsible for cracking Nazi spy codes, CRRU has been getting results—not only for FBI cases but also for local, state, and federal investigators who request our training and assistance.
“We’ve evolved with the crime trends over the years,” Olson said, “but at the same time we’ve kept our previous missions. As long as there are criminals,” he added, ”there will be a need for cryptanalysts.”


The meanings of the coded notes (above and below) remain a mystery to this day. | View larger versions (right click and save the files to enlarge further).


On June 30, 1999, sheriff’s officers in St. Louis, Missouri discovered the body of 41-year-old Ricky McCormick. He had been murdered and dumped in a field. The only clues regarding the homicide were two encrypted notes found in the victim’s pants pockets.
Despite extensive work by our Cryptanalysis and Racketeering Records Unit (CRRU), as well as help from the American Cryptogram Association, the meanings of those two coded notes remain a mystery to this day, and Ricky McCormick’s murderer has yet to face justice.
“We are really good at what we do,” said CRRU chief Dan Olson, “but we could use some help with this one.”
In fact, Ricky McCormick’s encrypted notes are one of CRRU’s top unsolved cases. “Breaking the code,” said Olson, “could reveal the victim’s whereabouts before his death and could lead to the solution of a homicide. Not every cipher we get arrives at our door under those circumstances.”

To move the case forward, examiners need another sample of murder-victim Ricky McCormick’s coded system—or a similar one—that might offer context to the mystery notes or allow comparisons to be made.

The more than 30 lines of coded material use a maddening variety of letters, numbers, dashes, and parentheses. McCormick was a high school dropout, but he was able to read and write and was said to be “street smart.” According to members of his family, McCormick had used such encrypted notes since he was a boy, but apparently no one in his family knows how to decipher the codes, and it’s unknown whether anyone besides McCormick could translate his secret language. Investigators believe the notes in McCormick’s pockets were written up to three days before his death.


Over the years, a number of CRRU’s examiners—who are experts at breaking codes—have puzzled over the McCormick notes and applied a variety of analytical techniques to tease out an answer. “Standard routes of cryptanalysis seem to have hit brick walls,” Olson noted. Our cryptanalysts have several plausible theories about the notes, but so far, there has been no solution.
To move the case forward, examiners need another sample of McCormick’s coded system—or a similar one—that might offer context to the mystery notes or allow valuable comparisons to be made. Or, short of new evidence, Olson said, “Maybe someone with a fresh set of eyes might come up with a brilliant new idea.”
That’s where the public comes in. The FBI has always relied on tips and other assistance from the public to solve crimes, and although breaking a code may represent a special circumstance, your help could aid the investigation. Take a look at McCormick’s two notes. If you have an idea how to break the code, have seen similar codes, or have any information about the Ricky McCormick case, send them to us online athttp://forms.fbi.gov/code or write to CRRU at the following address:
FBI Laboratory
Cryptanalysis and Racketeering Records Unit
2501 Investigation Parkway
Quantico, VA 22135
Attn: Ricky McCormick Case
There is no reward being offered, just a challenge—and the satisfaction of knowing that your brain power might help bring a killer to justice.
“Even if we found out that he was writing a grocery list or a love letter,” Olson said, “we would still want to see how the code is solved. This is a cipher system we know nothing about.”

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