There's No Way bin Laden's Alive. How Do we Know? DNA

Friday, May 06, 2011 - 04:44 PM


When President Obama made the announcement this week that U.S. Navy Seals had killed Osama bin Laden, the first question everyone asked was, How can he be so sure?

The answer: DNA.

As a criminal defense attorney, legal analyst and journalist who covered the innocence movement from its inception, I have long studied the DNA as a tool for exoneration, and identification.

So when I heard the government say it had a DNA match for bin Laden, I had a fundamental question: Match to what?

It was not that I doubted the time frame. I have covered the science of DNA and it’s use in the courts, for the last fifteen years, as DNA collection, testing and analysis evolved by leaps and bounds.

DNA analysis that once required weeks can now be performed in less than 24 hours. The process of extracting and purifying DNA can be done in less than an hour. Analysts need only a few hours to amplify, analyze and match the samples.

Which takes us back to the match: What was the reference sample on file for Osama bin Laden? In a typical case, involving rape or murder, a test sample of DNA from the crime scene would be compared with a reference sample already on file from the suspect to see if they matched. But this was not your run-of-the-mill case and this was not your typical suspect. Presumably, there was no reference sample on file for Osama bin Laden.

Bin Laden was unique in his status at the very top of the world's Most Wanted List; but he was just like the rest of us in relation to the human genome. His unique genetic code was shared with his parents and siblings. Think about it: Our parents are the ones who give us our DNA, to begin with. So the DNA swabs collected from the body in Pakistan would have been matched with reference samples previously collected from bin Laden's relatives.

Now it was starting to make sense.

It has been widely reported that the government collected DNA from bin Laden's half-sister, who died of brain cancer a year ago at Massachusetts General Hospital; after her death, government officials reportedly took some of her brain tissue for genetic testing.

So, that’s the DNA “match.” A close “match” identified Osama bin Laden with an extremely high probability of accuracy.

This is the famous (or infamous) 99.9 percent number, we hear so often in court. In the case of Osama bin Laden, the government is 99.9 percent sure the dead man is bin Laden because they compared his DNA to that of bin Laden's late half-sister. The results speak to the probability of a relationship between the two people, not the actual identity of the dead man.

To be 100 percent certain, the government would have had to compare Osama bin Laden to Osama bin Laden. And to do that, it would have needed a previously obtained bin Laden sample (say a hair plucked off his head by one of the two western journalists who interviewed him, or a fingernail clipping provided by an al Qaeda operative working with the CIA – unlikely scenarios, to say the least).

What we have instead is a DNA test comparing the profile of the man shot in Pakistan with a bin Laden family member. The result is a likelihood ratio. Taken together with bin Laden’s wife’s idenfication and photographic evidence, the proof was strong enough for President Obama to deliver his dramatic address to the nation late Sunday night.

Will we ever know for sure? 100 percent? Probably not, given that the body has been buried at sea. In some wild scenario, an original source reference sample could turn up. But I wouldn’t count on it. The government's 99.9 percent is good enough for the scientific community, and it's good enough for me. But if history is any guide, that one in one zillionth chance that Osama bin Laden is still alive will be just enough to satisfy conspiracy theorists for years to come.

Jami Floyd is an attorney, broadcast journalist and legal analyst for cable and network news, and is a frequent contributor to WNYC Radio. She is former advisor in the Clinton administration and served as a surrogate for the Obama campaign on legal and domestic policy issues. You can follow her on twitter.


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Comments [5]

Nick from Jersey

Hey Al, you're wrong. 100% wrong (not 99.9%)!

Ok, besides the overwhelming DNA evidence, the fact that the Americans, Pakistanis, and Al-qaeda themselves are admitting he is dead just solidifies it even more. You are delusional if you think this guy is still alive.

I will agree that the US government and other world powers lie constantly (Christ, the Pentagon released about 5 different stories about the assassination of OBL) but the plain and simple truth is that he is dead as Vaudeville. What is even better is that there is revolution in the Arab countries, and almost all of them are in flat out rejection of the kind of ridicuous, stone-age, fascist style theocracy that OBL dreamed of. He and his ideology are dead, al-qaeda is on the run. Hahaha, they vow revenge? Good luck guys, good luck.

May. 10 2011 02:00 PM
Aljamal from It does not matter

Conspiracy... Solomon? what a coincidence that Obama's popularity as so low eh! and why the government does not want to show his picture? did they destroy all his face and body that hi was unrecognisable? To identify somebody through a genetic test, they need to check the mitocondrial DNA, that only is preserved through his mother line. Imagine that Osama's mother did have extra offspring. What a disgrace for his father eh! by Islamic law, he should kill her. So it´s a bit unrealistic!

The news says:

"After being identified, the terrorist's body was flown from a U.S. base in Afghanistan to an American warship, where it was buried at sea in a traditional Islamic ceremony.

However, the decision to dispose of his remains at sea within 24 hours led to inevitable speculation and conspiracy theories that the U.S. authorities were trying to cover up the true identity of the man killed."

So, why buries him so quickly? why they didn´t show any images of that! why they wanted to have a secret ceremony? if you are claiming such a big new, after pursuing him for 10 years, what a better prove to the world than to show everything? We already know that the USA government does things as in the far west, like cowboys.

So if the TV, or US president tells you that something is true, you believe it blindly? You have a brain to think and contrast information (already filtered by media) and try to understand the interests behind. If you don´t know it! what you see and hear through the TV is already planed ahead before you see it or hear it. So, what is the truth? we will never know

We were told that Iraq did have weapons of mass destruction and for this, a war was created. US has more weapons of mass destruction than any nation in the world and from on side, they claim to help in removing them, but for other they still keep them. I understand that the most powerful nation in the world must have the latest weapon to threaten those that dare to go against the US. This is the testosterone way of thinking. We all know that the US government are a bunch of liars and you can´t deny it, as the evidence say so!

If you are from USA, you should start be ashamed of what your politicians are doing. I am ashamed to see mine, they only want power and money. They don´t care about us, the civilians. They live in another world and neither you nor I will have the chance to see.

Osama is alive and by now, probable with plastic surgery to pass unnoticed. Mmmm, DNA test on a half sister... what a laughter!

May. 09 2011 09:02 PM
Solomon Kleinsmith from Omaha, NE

This is actually a pretty good analogy to just about every conspiracy theory that gets around... that something amounting to a fraction of a percent of a chance of truth is something worth believing in, when an incredibly overwhelming tidal wave of evidence to the contrary says otherwise.

May. 09 2011 05:27 PM

The premise that DNA Evidence from bin Laden's half sister was used to prove the government killed the right person is wrong because ABC News has reported that although investigators had subpoenaed a DNA sample from Massachusetts General Hospital in Boston, where that half sister of bin Laden’s had died of cancer a spokesman for the hospital said it hasn’t turned up any evidence she was ever a patient there, nor that her genetic information was subpoenaed.

May. 06 2011 11:50 PM
Aljamal from It does not matter

What a prove! DNA. Eh! folks, to start -Bin Laden was used to live in the USA. He left samples of DNA all over and it was really simple to pick up a sample. Furthermore, with biological techniques, one can replicate his DNA, as long as Osama´s DNA was stored in a data base. DNA sample does not prove he is dead, special coming from the American administration.

To carry on, no one did see Osama´s dead body, as we all saw Saddam Hussein's hanging. What a trophy for the Americans to show off their trophy to the world. After being incompetents for almost 10, in finding a person, they come and say: "we killed Osama Bin Laden" and the prove they (Obama´s government) have is his DNA.

I don´t truest the American Goverment at all! neither the Russian, the Chinese, the big super powers. What they want is to gain more power and to be able to do whatever they want without being accused of doing so.

Open your eyes and don´t let the media poison your coherent mind. The bigger picture of what is happening is bigger than what we can see in our normal lives. There is not justice, no human rights, no boundaries to achieve a greater purpose, even thought it means that lie to the world. They did it before, they are doing it right now and they will still do. Believe it or not! wake up!!!!

May. 06 2011 08:42 PM

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