A funeral mass was held for Bill Phillips at Our Lady of Mercy Catholic Church in Potomac, Md.
Phillips was a prominent attorney and lobbyist in Washington, D.C. He served on the staff of the former Alaska senator for five years.
He was on a fishing trip with Stevens when their plane crashed on a remote mountainside in southwest Alaska. Three other people were also killed.
Phillips' 13-year-old son, Willy Phillips, was on the fishing trip as well and is one of four survivors of the crash.
Investigators are still searching for the cause.