In an upcoming juvenile-sex-abuse case in San Diego [a child protection hearing to determine if the minor should stay in the home of the custodial parent accused of sexual abuse], the defense is hoping to get an fMRI scan, which shows brain activity based on oxygen levels, admitted to prove the abuse didn't happen.
The technology is used widely in brain research, but hasn't been fully tested as a lie-detection method. To be admitted into California court, any technique has to be generally accepted within the scientific community.
The company that did the brain scan, No Lie MRI, claims their test is over 90 percent accurate, but some scientists and lawyers are skeptical.... The company's report says fMRI tests show the defendant's claim of innocence is not a lie.
Laboratory studies using fMRI, which measures blood-oxygen levels in the brain, have suggested that when someone lies, the brain sends more blood to the ventrolateral area of the prefrontal cortex. In a very small number of studies, researchers have identified lying in study subjects with accuracy ranging from 76 percent to over 90 percent (pdf). But some scientists and lawyers like [Stanford law professor Hank] Greely doubt that those results will prove replicable outside the lab setting, and others say it just isn't ready yet....
[On the other hand,] even if the science behind a technology isn't fully established, Brooklyn Law School's Edward Cheng, who studies scientific evidence in legal proceedings, said it might still be appropriate to use it in the courtroom.
"Technology doesn't necessarily have to be bulletproof before it can come in, in court," Cheng.
He questioned whether society's traditional methods of lie detection, that is to say, inspection by human beings, is any more reliable than the new technology....
Read the whole article -- very interesting stuff both on the possible problems with the technology and some of the legal questions it raises (on which I can't opine, since I'm not an expert in scientific evidence law). Thanks to GeekPress for the pointer.