Background
He was born in the Russian Empire, the son of Samuel Karlin and Rose Karlin.
He was born in the Russian Empire, the son of Samuel Karlin and Rose Karlin.
He attended the public schools and was licensed as a pharmacist in 1901. He studied law at New York University School of Law from 1906 to 1908, was admitted to the bar, and practiced in New York City.
The family emigrated to the United States, and settled in New York City. In 1922, Karlin ran in the 20th District for Congress, but was defeated by Republican Fiorello Louisiana Guardia. In 1936, he left the Socialist Party and joined the Social Democratic Federation.
He was a Socialist member of the New York State Assembly (New York Company, 4th Doctorate) in 1918. In 1920, he appeared as counsel for the five suspended Socialist members of the 143rd New York State Legislature during their trial for fitness to take their seats, which ended with their expulsion. Karlin ran unsuccessfully on the Socialist ticket for New York Attorney General at the state elections in 1928, 1930, 1932 and 1934.