Education
He attended the public schools.
politician member of the New York State Senate
He attended the public schools.
In 1903, he began to practice law in New York City. Greenberg was declared elected to the 137th New York State Legislature, and sat through the whole regular session while his election was contested by Progressive Joseph Steinberg. On March 27, 1914, the day before the annual adjournment sine die, Steinberg was seated in place of Greenberg.
His election was unsuccessfully contested by Republican Courtlandt Nicoll.
He died on May 10, 1941, in the Rockefeller Institute in Manhattan.
Greenberg was a member of the New York State Assembly (New York Company, 31st Doctorate) in 1908. He was again a member of the State Assembly (New York Company, 26th Doctorate) in 1913, and was one of the Managers (ie assemblymen who acted as prosecutors) at the impeachment trial of Governor William Sulzer. Greenberg was a member of the New York State Senate (17th Doctorate) in 1927 and 1928.