 In 1913, as a member of the Washington Senators, Ainsmith was suspended by Ban Johnson for throwing dirt at umpire Peter McLaughlin.On April 21, 1915 Ainsmith was sentenced to 30 days at Occoquan Workhouse for an assault on a streetcar operator in Washington, D.C.

During World War I Ainsmith was drafted into the United States armed forces.He appealed to the United States Department of War for an exemption from the draft, but Secretary of War Newton D. Baker ruled that baseball was not an exempt occupation.