Brain Imaging and Criminal Law

by Astrid Fiano, DOTmed News Writer | May 04, 2009

Rehkopf explained that there are no evidentiary challenges to brain imaging if one is versed and prepared with the laws of evidence. "First, the image must be relevant to something at issue in the trial - if the Defendant does not testify, his "truth" isn't at issue. Juries "see" better than they hear, so a blow-up of an image, showing particularized "damage" to an area of the brain, with a "normal" brain image next to it, is powerful proof. If you're a prosecutor and need to prove injury, or level of injury, or even sometimes "causation" e.g., "shaken baby" cases, that is very good evidence. But, it's also useful for the defense, e.g., the "injury" suspected may not be what the theory is. I had a case where the imaging showed that it was a blood clot from an unrelated surgery that caused the death, not getting hit in the head."
Rehkopf explained that the courtroom usages of such imaging is to show one (or more) of the following: (a) specific injuries to a part of the brain; (b) "bleeds" affecting larger areas of the brain; (c) swelling, to include compression of the brain stem; (d) other artifacts, e.g., clots, clogs or irregularities in development; (e) normal brain functioning, etc. "It is very useful in those cases where it is used to corroborate neuropsychological testing results."

In addition, Rehkopf notes that imaging is frequently used "as mitigation evidence in capital cases to demonstrate prior injuries, lack of development of key portions of the brain, tumors, etc. The key is linking it to conduct or reason and it is usually done in conjunction with a neuropsychological expert."

Recently in New York State, brain imaging was used in the defense of Peter Braunstein, who was convicted of kidnapping, sexual abuse, robbery, and other felonies in 2007, and sentenced to 18 years to life in prison. His defense attorneys used a brain scan to indicate his actions were due to mental illness. Rehkopf notes of the case, "His lawyers were taking a leap, which the prosecution's experts shoved down their throats that the imaging could "demonstrate" schizophrenia - but, there's no known correlation, just hypothesis. Besides, that case was not focusing on the "who did it" but rather, on an insanity defense, which is notoriously difficult to do in New York [and most places] post-Hinckley. I mean, his lawyers tried, but it was a long-shot from the very beginning. The concept requires acceptance of the hypothesis that there is a physiological aspect to insanity -- there could be as a result of injury or disease, but then you have to lay that foundation. It's a very rare case from my knowledge, primarily, at least in criminal cases, because of the Daubert issue. Braunstein's lawyers got around that by having the mental health people diagnose him, and then used the imaging as 'demonstrative' evidence to try and corroborate their diagnosis. But, his 'problem' was, as with most schizophrenics, he was lucid and rational at times."