Education
Born in Brooklyn, New York, Magner attended the public schools. He graduated from Saint Xavier College in 1880 and from Columbia University, New York City, in 1882.
United States representative politician
Born in Brooklyn, New York, Magner attended the public schools. He graduated from Saint Xavier College in 1880 and from Columbia University, New York City, in 1882.
He taught in a public school in Brooklyn. He studied law. He was admitted to the bar in 1883 and commenced practice in Brooklyn, New York, the same year. Magner was elected as a Democrat to the 51st, 52nd and 53rd United States Congresses, holding office from March 4, 1889, to March 3, 1895.
He resumed the practice of law, and served as corporation counsel of the Borough of Brooklyn in 1913-1917.
He died, after a long illness, in the Hotel Bossert, Brooklyn, New York, December 22, 1945. He was interred in Holy Cross Cemetery.
He was a member of the New York State Assembly (Kings Company, 6th Doctorate) in 1888.