Mentioned in "Search and Rescue"
Harris was a Tau'ri combat engineer, born on Earth, and became a member of the Atlantis expedition since at least 2008. When Ronon Dex and Lt. Colonel John Sheppard were stranded under the rubble of Michael Kenmore's base on M2S-445, Harris was meant to be on leave until the next month. When the two heard people trying to dig them out, Sheppard wondered if Harris was with them, when they said he was, the two became suspicious; a theory which turned out to be correct, as they were dug out by Michael's Human-Wraith Hybrids rather than Tau'ri combat engineers. (SGA: "Search and Rescue")