(CNN) Robert M. Morgenthau, the longtime Manhattan district attorney who set the "gold standard" for prosecutors and was the model prosecutor for the TV series "Law & Order," has died at the age of 99.

Morgenthau took office in 1975 and ran the district attorney's office for 35 years until the age of 90, making him New York City's longest serving district attorney.

In that time, he navigated the New York City fiscal crisis of the 1970s, the crime boom of the '80s and '90s and the post 9/11 era in the 2000s, all the while racking up high-profile prosecutions of celebrities, mobsters, terrorists, money launderers and Wall Street fraudsters.

Morgenthau created 34 bureaus and units within the DA's office specializing in labor racketeering, identity theft, firearms trafficking, Asian gangs and cold cases, among others. The sex crimes unit, in its infancy when Morgenthau took office, grew into the prototype for similar units across the country, CNN wrote in 2010

His office became the model for "Law & Order," the New York City police and legal drama created by Dick Wolf that ran from 1990 to 2010. The show's first fictional district attorney, Adam Schiff, played for 10 years by actor Steven Hill, was said to be based on Morgenthau.

Read More