SACRAMENTO — Scans of convicted killer Richard Hirschfield’s brain show extensive damage that put him at increased risk for social and emotional dysfunction since his birth, a forensic psychiatrist testified this morning in Sacramento Superior Court.
“These are very abnormal scans,” said Douglas Tucker, a stand-in for University of Pennsylvania professor Ruben Gur, who prepared a report based on his study of Hirschfield’s brain scans. Tucker described the results as “grossly pathological. …I have never heard of that degree of functional deficiency.”
Tucker testimony came on the second day of the penalty phase for Hirschfield, 63, who has been convicted of kidnapping and killing UC Davis student John Riggins and Sabrina Gonsalves on Dec. 20, 1980. Prosecutors are seeking the death penalty.
The defense, hoping for a sentence of life in prison without the possibility of parole, says Hirschfield endured a “chaotic” abusive childhood that explains and mitigates his later criminal conduct.
In his testimony, Tucker said Hirschfield’s brain damage had likely been present since birth or early childhood. He described the presence of both structural and functional deficiencies in the amygdala, an interior portion of the brain involved in emotional processing and behavior control.
As a result, Hirschfield was at increased risk for antisocial behavior, and his ability to learn from punishment also was impaired, Tucker concluded, though he noted that neither he nor Gur interviewed Hirschfield as part of the evaluation.
“This is a clear-cut structural abnormality,” Tucker said. “These are very clearly pathological levels of tissue loss.”
Deputy District Attorney Dawn Bladet is expected to cross-examine Tucker this afternoon.
Earlier, she asked Judge Michael Sweet to impose sanctions on defense attorneys in the case, who she said failed to disclose to her portions of Gur’s report until Tucker had already taken the witness stand.