SAN FRANCISCO (CN) - The chemical composition of lethal poisons took center stage at an evidentiary hearing Monday in a case against a San Francisco political consultant accused of possessing a weaponized biological toxin.
Authorities arrested Ryan Kelly Chamberlain in June 2014 after a three-day FBI manhunt prompted by weeks of surveillance after the discovery of records of poisons purchased on the dark Web and shipped to Chamberlain. Chamberlain had worked as a publicist for California Lt. Gov. Gavin Newsom when Newsom ran for mayor of San Francisco.
U.S. District Judge Vince Chhabria refused in August to dismiss the charges against Chamberlain, although Chamberlain's attorney Jodi Linker argued that the FBI's confiscation of vials containing crushed rosary peas is not sufficient evidence that Chamberlain intended to poison anyone.
Linker argued that the person who sent Chamberlain sent the crushed peas - which can be used to make the highly toxic substance abrin - instead of chemically purified abrin.
At Monday's hearing, expert witness Christa Mason took the stand, testifying about the possible degree of abrin concentration in the vials. Mason is a forensic examiner at the FBI's Chemical, Biological, Radiological and Nuclear Sciences Unit.
During her testimony - mostly founded on highly specialized studies in chemistry and requiring the frequent use of a calculator - Chhabria stopped her frequently for clarifications.
"From what has been presented so far, I do not yet have any understanding of how it was concluded that the vials contained 2.8 milligrams of abrin, or who drew that conclusion," Chhabria said.
Other questions included how many rosary peas would have to be ground in order to yield such a concentration - approximately 3.73, Mason said - and to what degree cancer patients can tolerate the substance.
Evidentiary hearings are expected to continue throughout the week.
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