In 1911 he was charged with criminal negligence and cowardice by Dr. R.A. Toms, Justice of the Peace of Tonawanda, New York. Harold W. Bell was killed when Burnham's motorboat, the Dixie IV, ran ashore while competing in championship races here on September 16, 1911.
Burnham married, in June 1907, Lillian Richardson Baldwin (1882-1967), who was a niece of the opera star Lillian Nordica. They divorced in 1912 and had two children: Frederick W. Burnham (born 1908) and Annette Patricia Burnham (1910-1966).
- "Motor Boat Dixie IV. Wrecked On Rocks. Champion Craft Makes Wild Dash Into Crowd on Niagara River and Hurts Three". New York Times. September 16, 1911. Retrieved 2010-11-09.
Frederick K. Burnham's speedy hydroplane, which successfully defended the Harmsworth Cup at Huntington, L.I., and on Friday won the championship of the United States on the Niagara River course, to-night lies a wreck on a narrow ridge of rock between the Niagara River and the Erie Canal, off Riverside Park.
- "Justice Charges Burnham with Negligence and Cowardice in Bell Inquest". New York Times. October 20, 1911. Retrieved 2010-11-09.
Criminal negligence and cowardice are charged against Frederick K. Burnham in the findings of Dr. R.A. Toms, Justice of the Peace of Tonawanda, who conducted the inquest into the death of Harold W. Bell, one of the persons fatally injured when Capt. Burnham's motorboat, the Dixie IV., ran ashore while competing in championship races here on Sept. 16.