What is truth serum?

Indian officials plan to inject captured Mumbai terrorist with the "truth serum," sodium pentothal, but history tells us that the technique isn't up to the task















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INTERROGATION CHAIR: Can "truth serum" make criminals fess up? Image: © iStockPhoto / Stefan Klein

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The baby-faced gunman of Mumbai, Azam Amir Kasab,  now in the custody of Indian police, is the sole surviving attacker in the three-day rampage that began on the night of November 26 and left more than 170 people dead and scores of others injured.

After the attacks, Indian officials immediately began pointing fingers at longtime rival, Pakistan, as the source of the 10 militants—a charge that Pakistan President Asif Ali Zardari disputed last night on CNN. During police interrogations, Kasab himself claimed to hail from the Punjab region of Pakistan and to have trained with the Pakistan-based extremist group, Lashkar-e-Taiba.

Of course, Kasab could be making this all up. The only way that interrogators can tap a man's memory is to ask him. But what if the person is unwilling to spill the beans or, at least, the real ones? If only there were only a way to plug a USB cable to the back of Kasab's head and just download the experiences.

While such technology may be the stuff of science fiction, Indian government officials have announced they will employ another technique that seems to leap from the pages of a 1940s pulp novel: truth serum. Also known as narcoanalysis, administering psychoactive drugs for interrogation purposes has been around for just under a century, but it has been viewed with skepticism from the start. Indeed, the practice is banned in most democracies, and evidence obtained from such an interrogation would have a hard time making it into an American court. 

But could "truth serum" reliably extract the truth from this man and other criminal targets? We asked Alison Winter, a science historian at the University of Chicago, who has studied the origins and applications of truth serum.

What does the term "truth serum" mean?
That's a term that was used to describe the use of certain drugs, most commonly barbiturates like sodium amytal and sodium pentothal, to try to extract truthful statements from people about their past experiences.  What the term really meant was that the people who used the serum believed that it made people unable to censor themselves and they would just empty their memories into a narrative statement.

Who discovered these effects?
In the mid-1910s, Dr. Robert House was an obstetrician who noticed that the popular obstetric anesthetic drug, scopolamine, also known as twilight sleep, would put his patients into a state where they would deliver information in a way that seemed automatic.

He didn't want to use it in interrogation, for the purpose of getting people to admit to criminal acts, so this is a quite different beginning from the association we have now. At the time, he wanted to use it to provide support for claims people made about their innocence -- not their guilt.  If somebody said 'I wasn't at the crime, I was in the library but nobody saw me,' then, perhaps, this would give support for the claim, because you would think they could not lie under the drug's influence.

It was only later when other people used these drugs that they got the reputation for having the power to force people to provide information against their will.

How did they begin to be used for interrogation?
In the 1930s, there were these committees to evaluate corruption in American policing, and it first came out that police were using these drugs in interrogations to get suspects to incriminate themselves. But there's not a lot of documentation of that.



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  1. 1. jinchoung 06:14 PM 12/6/08

    why is it STILL so unclear? if it is not a toxic or overtly harmful drug, why don't they just TEST IT? do an experiment with a control and get people to remember an answer to a non yes or no question (that wouldn't be subject to common knowledge - e.g. what color underwear did you wear tuesday?) and instruct them to do their level best NOT to reveal it. give the experiment group (of 100 people say...) the drug and then see if they reveal the info more times than a group given a placebo. SOOOOoooooo easy to test. WTF?

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  2. 2. piedpiper in reply to Scientz 09:27 PM 12/6/08

    There's a spelling mistake in the last commant.

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  3. 3. jgrosay 09:17 AM 12/7/08

    A technique used for obtaining unwanted confessions is REM sleep deprivation. After a few days on it, you tell the whole story in exchange of a candy or a nap

    Reply | Report Abuse | Link to this
  4. 4. ZenaV 08:18 PM 12/7/08

    I have a list of people I'd like to see on these drugs...

    Reply | Report Abuse | Link to this
  5. 5. jstepp590 11:50 AM 12/8/08

    There is a new form of lie detector test called a fMRI lie detector that is highly accurate. It is based on watching brain activity in real time. In the brain, a persons imagination and memory are in two different places so if someone is lying it is immediately obvious because of where the activity is taking place. Some reports place the accuracy at over 99%, with the only false reading happening when the data is read incorrectly by the operator. This technology, imho, should be in widespread use by law enforcement around the world and should be mandatory when peoples lives are at stake. It would also do wonders for filtering out prisoners who have been falsely convicted.

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  6. 6. inboulder 12:29 PM 12/8/08

    This article didn't present any clear opinion or information whatsoever. Where are the studies?

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  7. 7. redfoxone 01:58 PM 12/8/08

    I dunno but rest assured the US Government uses it.

    hess
    www.online-privacy.se.tc

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  8. 8. pinginfan in reply to jstepp590 05:10 PM 12/8/08

    Doing that would be a clear violation of the fifth amendment.

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  9. 9. science+music=cool in reply to jgrosay 02:38 PM 12/9/08

    under geneva convention isnt getting somebody to admit to something well forcing a confession whatever. isnt that a violation of human rights. now agree or disagree but its still in there. so even if you had a magic potion that would make you tell people everything then its still a violation of basic human rights. now im english but its still in the america constitution like that guy/ girl says. fifth amendment. magic potion or not you cant use it by the very definition of unaliable rights. having said that i would so love to do research into this kind of thing, how it works on the brain ectect. isnt that what they were originally tying to do with LSD?

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  10. 10. science+music=cool 02:41 PM 12/9/08

    yeah id like to see the studies. and the stuff on the new lie detector. how does it work if you actually believe what you are saying. i mean if you are lying on the spot then yes i can see it working but how if its prefabricated?

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  11. 11. ajhil in reply to jinchoung 03:34 PM 12/10/08

    This is NOT unclear! Work with pychoactive drugs in numerous different contexts have demonstrated beyond any shadow of a doubt that none of them specifically promotes truth-telling. Most of these drugs are depressants, which can reduce inhibitions by depressing those brain functions first. In doing so they make (some) people (some of the time) more talkative than they ordinarily might be; however, these people are just as likely - in fact, sometimes more likely - to invent the things they say as to tell the truth.
    Case in point: do you consider the things that people say when they're drunk to be especilly truthful or reliable? Alcohol is no different in principle than scopalamine or barbiturates or benzodiazepines or anti-psychotic drugs like Thorazine. None of them is a genuine "truth serum."
    This is an urban myth that is long overdue for the scrap heap!

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  12. 12. ajhil in reply to jinchoung 03:36 PM 12/10/08

    This is NOT unclear! Work with pychoactive drugs in numerous different contexts have demonstrated beyond any shadow of a doubt that none of them specifically promotes truth-telling. Most of these drugs are depressants, which can reduce inhibitions by depressing those brain functions first. In doing so they make (some) people (some of the time) more talkative than they ordinarily might be; however, these people are just as likely - in fact, sometimes more likely - to invent the things they say as to tell the truth.
    Case in point: do you consider the things that people say when they're drunk to be especilly truthful or reliable? Alcohol is no different in principle than scopalamine or barbiturates or benzodiazepines or anti-psychotic drugs like Thorazine. None of them is a genuine "truth serum."
    This is an urban myth that is long overdue for the scrap heap!

    Reply | Report Abuse | Link to this
  13. 13. ajhil 03:36 PM 12/10/08

    This is NOT unclear! Work with pychoactive drugs in numerous different contexts have demonstrated beyond any shadow of a doubt that none of them specifically promotes truth-telling. Most of these drugs are depressants, which can reduce inhibitions by depressing those brain functions first. In doing so they make (some) people (some of the time) more talkative than they ordinarily might be; however, these people are just as likely - in fact, sometimes more likely - to invent the things they say as to tell the truth.
    Case in point: do you consider the things that people say when they're drunk to be especilly truthful or reliable? Alcohol is no different in principle than scopalamine or barbiturates or benzodiazepines or anti-psychotic drugs like Thorazine. None of them is a genuine "truth serum."
    This is an urban myth that is long overdue for the scrap heap!

    Reply | Report Abuse | Link to this
  14. 14. ajhil 03:42 PM 12/10/08

    Sorry about the multiple posts. My mistake!

    Reply | Report Abuse | Link to this
  15. 15. monkeyrave in reply to science+music=cool 03:18 PM 12/11/08

    Yes I believe that they were trying to do this with LCD and with any type of spychoactive or hallucinogen drug; just because you cannot control what you do sno how can you lie or tell the truth.For this reason;under the influence of these drugs you are inclined to talk when asked something but the answer wont always be right.Althought there might be alot of answers that a person might give the truth is bound to be in there obscured by all the other stuff the person might have said.And yes I love studying drugs and the effects they have on the human body.They are so interesting!

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  16. 16. Chithra KarunaKaran 06:31 PM 12/12/08

    What troubles me is that the police in India, a democracy, is being reported as planning to use a so-called "truth serum" drug sodium pentathol to elicit information from the captured terrorist.

    This is troubling. He certainly should be questioned but any form of coerced confession much less torture, should be completely unacceptable.

    The Indian media is not displaying its investigative responsibility by failing to provide any reports on the condition of this political prisoner.

    Chithra KarunaKaran
    Ethical Democracy As Lived Practice
    http://www.EthicalDemocracy.blogspot.com

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  17. 17. pratandon 05:28 PM 12/15/08

    Recently there was a case in India where a teeenage girl was murdered and her dentist father was being falsely implicated for this heinous crime. At the same time, three other persons were arrested for the same crime and were placed under this test. Now this test was administrated at different places/ time to these three persons. However all of them came up with a very similar narration of the sequence of events when placed under this so called truth serum test. Is there a likelihood that all three persons can come up with a similar story, just because of 'suggestibility' factor? Please enlighten me on this.

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  18. 18. verdai in reply to jstepp590 05:26 PM 1/23/09

    say!
    that must be wonderfull, we have waited so long to overcome this problem.
    I sure hope it is true.
    Seeing many articles about brain scanning, etc,...
    such use would be worth all the others,
    in this world-

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  19. 19. verdai in reply to verdai 05:35 PM 1/23/09

    The MRIs, or what ever, that is; not any drugs which as we all know cannot control the slimey human speech. or is that reflection true?

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  20. 20. verdai 05:37 PM 1/23/09

    to and re: jstepp

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  21. 21. verdai 05:42 PM 1/23/09

    to and re: jstepp
    the MRIs, whatever, that is; since we all know that drugs cannot control the slimey human spoken word.
    Any better reflection of truth would be a great advance.

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  22. 22. dorothymarie18 07:27 PM 7/6/09

    I would really like to know if it really works..and where would I go to get it done?

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