He studied at the Electro-Therapeutic Institute, and became a "medical electrician"[1] and manufacturer of surgical instruments.
In November 1910, he ran on the Republican ticket for the New York State Assembly (Kings Co., 6th D.), and polled 3,533 votes, but was defeated by the incumbent Democrat John H. Gerken who polled 3,586 votes.
[2] In November 1912, Karpen ran on the Progressive and Independence League tickets for the State Assembly (Kings Co., 21st D.), and polled 1,674 votes, but was defeated by the incumbent Democrat Harry Heyman who polled 2,000 votes.
[3] In November 1913, Karpen defeated Heyman, and was elected as a Progressive, with Republican and Independence League endorsement,[4] to the State Assembly (Kings Co., 21st D.).
Karpen died on July 27, 1936, at the home of his brother Clarence Alfred Karpen in Lynbrook, Nassau County, New York, of angina pectoris; and was buried at the Cypress Hills Cemetery in New York City.