Assistant US Attorney Gregory Broderick stumbled badly in his cross-examination of Dr. Carl Hart in federal evidentiary hearings to determine the constitutional basis of the federal Schedule I classification of cannabis, appearing at times to even tacitly endorse the idea that cannabis has medical value. In hearings conducted on October 27th by the Hon. Kimberly Mueller in the federal Eastern District of California in the matter of US v Schweder, attempts by US Attorneys to paint Hart – who teaches neuroscience at Columbia University and sits on an advisory board to the National Institute of Drug Abuse (NIDA) – as a researcher blinded by his personal biases blew up, at times embarrassingly, in their faces.

In one dramatic example, Broderick asked Hart about the Diagnostic and Statistical Manual (DSM), which is published by the American Psychiatric Association and contains a definition of “substance use disorder” (AKA addiction) which has been regarded as definitive by courts. Noting that the substance abuse standard promulgated by the 4th edition of the DSM (the DSM-IV) results in an oft-quoted 9% rate of dependence among lifetime users of cannabis, Broderick requested Hart’s comment.

But Hart appeared to stun Broderick with his response that the newest version of the DSM, the DSM-V, explains that tolerance and withdrawal from cannabis are “normal symptoms to be expected of legitimate medical cannabis use” in states where it is legal. (This point was later expanded upon by the testimony of Dr. Philip Denny, another expert witness for the defense.)

Broderick tried to recover by bringing up some of Dr. Hart’s family history in an apparent attempt to show bias. Asking about the legal troubles of his adult son and other members of his family, Broderick tried to insinuate that these troubles had spurred Dr. Hart on to some kind of personal mission to legalize drugs. “I’m a black man in America,” Dr. Hart replied. “You’d be hard pressed to find someone like me who isn’t closely connected to someone” who has been through the penal system.

Nevertheless, Dr. Hart brushed off these and all other attempts by Broderick to make Dr. Hart’s testimony about Dr. Hart. In response to questions of whether certain propositions accorded with his opinion, Hart repeatedly and emphatically replied no: “It’s not my opinion,” the scientist said. “It’s what the evidence indicates.”

Broderick’s attempts to discredit Dr. Hart’s credentials backfired even worse. At one point, the prosecutor asked why Hart was an expert in medical matters when he doesn’t hold an M.D. (Hart’s PhD is in neuropsychopharmacology). “I teach at Columbia’s medical school,” Hart replied. “I train doctors.”

Soon after, when Broderick brought up the fact that the American Medical Association had released statements calling cannabis a “dangerous drug,” Hart replied: “Think about what you just said. The AMA committee reads research, such as what I conduct, to form their positions. So why would I go to them for their opinion?”

The intellectual mismatch between the two adversaries became so painfully apparent that at one point Broderick attempted a joke to relieve the tension. “I was a political science major,” Broderick protested. “Not neuroscience.”

But the joke was on him later in the examination when Broderick appeared to misunderstand some of the nuance of Hart’s explanations of NIDA operations. “I thought you were a political science major,” Hart retorted, as laughter exploded in the courtroom.