William Lynn may refer to: Billy Lynn (born 1947), former English professional footballer William Henry Lynn (1829–1915), Irish-born architect Msgr. William J. Lynn, Roman Catholic official on trial in 2012 in a conspiracy and endangerment/child sex abuse case in Philadelphia William J. Lynn III (born 1954), Deputy Secretary of Defense of the United States of America William Harkins Lynn (1888–1952), American actor who played Judge Gaffney in Harvey (1950)