Powerful lie detection tools may someday surpass the accuracy of the polygraph and permanently change how suspects are convicted -- and freed.

Imagine, a suspect is read words related to a crime while their brain is being scanned. A computer analyzes the data and informs the examiner if the suspect's memory holds information about the crime that only the perpetrator could know. The suspect would not even have to speak, for the examiner to know if the subject has exclusive knowledge of the crime. The guilty could be clearly identified and the innocent would be set free.

It's not science fiction. The technology and knowledge to scan your brain for the truth is already here and it is improving rapidly. Today, using current technology, a government can know with 90% accuracy if the person they are holding in custody is a spy. And it is available to the public. Finding out what happened in Vegas is now as easy as getting your spouse to lie down on an examination bed. (hint: tell them it's a massage table.)

I sincerely hope that when this technology arrives, it is offered as a choice, like our current lie detection methods, for the accused to be cleared of a crime--and the results are never revealed to a jury.

How will brain scan technology change society and our legal systems? Clearly, public debate concerning the proper use of lie detection technologies is needed to raise concerns about their premature and inappropriate use.