Harris is an unseen character in the TV series. He one of the leading members of the Sons of Jacob.
Before Gilead[]
When the future Commander Fred Waterford returns home one morning from a late-night meeting with the Sons of Jacob's full committee, he remarks to Serena Joy that both Colby and Harris were still being followed, most likely by the FBI.
After the President's Day Massacre[]
Nothing is known about Colby and Harris. But if they were later captured, it was most likely that they were either held in Hawaii or another US military prison.