Phippen was an airport cop approached by Shannon at Sydney Airport after Sayid had left his bag near her chair. ("Exodus, Part 1") Presumably, he took Sayid in for questioning. He was later seen releasing Sayid and apologizing for the inconvenience, to which Sayid sarcastically replied "I'm sure you are." ("Exodus, Part 2")
The character was credited as Airport cop, and his name was seen on his nametag.