Analysis of the evidence from the works of Origen, Eusebius, and Hegesippus concludes that the reference to “Christ” in Josephus, Jewish Antiquities 20.200 is probably an accidental interpolation or scribal emendation and that the passage was never originally about Christ or Christians. It referred not to James the brother of Jesus Christ, but probably to James the brother of the Jewish high priest Jesus ben Damneus.
Dr. Carrier also notes that:
[T]his article also summarizes a sufficient case to reject the Testimonium Flavianum as well (the other, longer reference to Jesus in Josephus), in that case as a deliberate fabrication (see note 1, pp. 489-90, and discussion of the Arabic quotation on pp. 493-94). And I cite the leading scholarship on both. So it’s really a complete article on both references to Jesus in Josephus.
It's wonderful to see Dr. Carrier produce what I consider to be the definitive smackdown of the Josephus arguments. The "James passage" never spoke of Jesus Christ, and as Dr. Carrier rightly concludes, the Testimonium is "100% Christian fabrication."
See also: The Case Against the Josephus Passages