The perjured testimony from Joseph Kopera, Maryland’s police ballistics expert witness who killed himself this month after being confronted with evidence that he had falsified his credentials continues to affect the cases in which he testified.
Maryland prosecutors and defense attorneys have said that revelations about Kopera’s falsified credentials could force new trials for some of the hundreds of people he helped convict in a career that spanned nearly four decades.
As reported in the Baltimore Sun, one defense attorney stated: “The point is not that the jury might have evaluated his conclusions differently if they had known that his knowledge was based only on ‘on the job training,’ although that is certainly a possibility. Rather, the point is that once a jury is aware that a state’s expert has utterly failed to abide by the oath given to all witnesses, the jury reasonably can conclude that the witness has little regard for the truth.”