U.S. v. Hill, -- F.3d --, 2014 WL 1663084 (4/28/14)(OK) - It was plain error to admit expert opinion that the defendant lacked credibility during a videotaped statement he gave when interrogated about a bank robbery. An FBI special agent was permitted to proclaim to the jury his training and expertise in identifying truth and deception. He improperly testified that he had never seen an innocent person say, as Mr. Hill did, that he would rather die than face charges. The expert opined that Mr. Hill's repeated invocation of God in support of his version of events indicated deceptiveness. Experts are not permitted under Rule 702 to testify about the credibility of another person - it is the jury's function to make credibility determinations. It does not matter that the defendant's statements that the expert assessed were made out of court. There is a reasonable probability that without the improper expert testimony, the outcome of Mr. HIll's trial would have been different; the government's evidence was not strong.