NEW YORK Immigration documents filed in 1961 cast doubt on whether Barack Hussein Obama Sr. was the presidents biological father and indicate federal officers were prepared to investigate whether the Kenyan was married to the presidents mother, Ann Dunham. Aside from the image of a long-form birth certificate released by the White House April 27, 2011 a document Sheriff Arpaios law enforcement investigation has found probable cause to believe is a forgery what documentary evidence is there that Barack Obama was the biological father?