Is it really Osama bin Laden who died?
That question arose immediately after news first broke of the world’s most wanted man being killed in a US special forces raid on the Pakistani garrison town of Abbottabad.
A female survivor is believed to have identified Osama’s body, possibly his wife, but that is obviously not credible confirmation. So, the US government offered an answer based on two technologies, face recognition and DNA testing.
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These were the results: 95% accuracy through face recognition and 99.9 “confidence” by testing the DNA (deoxyribonucleic acid, the blueprint for life, encoded in bits of DNA called genes) of the man they killed in the fortified Abbottabad compound.
None of these are as straightforward and error-proof as they sound, so if conspiracy theorists delve into the technology that’s been quoted, they could float plausible questions about Osama’s identity.
Let’s first deal with face-recognition technology, used globally at high-security establishments to establish identity—and in Hollywood thrillers.
Face recognition works by mapping various points on your face to create a biometric fingerprint. This is nothing more than computer code, so it needs to be precise. Even with the living, facial recognition poses some problems; with the dead it can get tricky.
A facial image taken from a slightly different angle can alter a biometric fingerprint. An image of a face that has lost some mapping point—such as an eyeball or disfigured nose, all possibilities during a gunfight—reduce the probability of a match.
A 95% match of identity is the top end of the scale. This means Osama’s face may have been intact, even if he was shot twice in the head (and once in his stomach), as the US now reports.
It also now emerges, according to a background briefing to the Associated Press, that facial-recognition technology first identified Osama from satellite pictures in September 2010, as he exercised in his Abbottabad compound. Can a face be recognized from a satellite? Isn’t this the stuff of movies?
Apparently, it’s now real.
Governments don’t usually acknowledge their technological trump cards. But the killing of Osama was an epochal event. The US inadvertently confirmed the existence of some cutting-edge technology to ensure the declaration of his death was credible.
While the face-recognition software the US military possesses is highly advanced and was vital in identifying Osama for the special-forces operation, it was of lesser use in conclusively proving to the world that it was him.
This is where DNA testing comes in, the gold standard for identification. It is particularly useful when dealing with body fragments, such as those found at the site of the twin towers of the World Trade Centre, plane-bombed by Osama’s men on 9/11.
“The notion that we were to reassociate potentially hundreds of thousands of remains—let alone identify them by comparing their profiles to perhaps tens of thousands of kin and effects profiles—was beyond daunting,” said W. Mark Dale, director of forensic services for the New York police department during and after 9/11. What worked for Dale and his people was DNA identification of these remains.
When John Brennan, assistant to US President Barack Obama for homeland security, said the DNA evidence provided a match with “99.9% confidence”, he meant that DNA identification works in probabilities, not certainties. A DNA match in Osama’s case refers to the probability of a relationship between two samples of genes.
A standard DNA test can take up to 20 hours to come up with a match, which means the US military has technology that can deliver the same answer much quicker.
The 99.9% probability also meant the US either had Osama’s DNA samples or it had access to one of his children.
DNA can be matched with some confidence to brothers or sisters. Osama had none. He had more than 50 half-brothers and sisters. DNA from half-brothers and sisters can provide a probability match of greater than 90%, but that would not do with Osama. Nothing is as reliable as DNA match with a parent or child.
With one of Osama’s sons reportedly killed in the raid, it could be possible that the US military used his DNA, combining that test with tests on previously gathered samples from Osama’s half-brothers and sisters scattered across the world.
It is also possible that US forces had Osama’s DNA on file, gleaned from a previous hideout or from the time he worked with US forces against the Soviet occupation of Afghanistan. Osama always escaped US forces, but they have scoured his old hideouts, which could have yielded a strand of hair, a drop of blood, a scraping of skin.
Much of this science is too arcane for the average rabble rouser. So, despite all its high technology, Obama is now considering a decidedly low-tech way of proving the US did indeed get their man—by showing the world a photograph of a dead Osama.
Samar Halarnkar is editor-at-large, Hindustan Times and Mint. This is a fortnightly column that explores the cutting edge of science and technology. Comments are welcome at firstname.lastname@example.org