New York Attorney General Letitia James expressed disappointment in the decision, and slammed the system as a whole saying ... "Current laws on deadly force have created a system that utterly and abjectly failed Mr. Prude."

She claims her office presented the most comprehensive case it possibly could and added ... "I know that the Prude family, the Rochester community and communities across the country will rightfully be disappointed by this outcome."

As we reported, 7 Rochester cops were suspended in September after video was released of the 41-year-old Black man being detained on March 23, having a hood placed over his head, and then pressed down on the ground.

Prude was held there for 2 minutes until cops realized he was unconscious. He was taken to the hospital and placed on life support, but died a week later.

The medical examiner ruled his death a homicide, caused by "complications of asphyxia in the setting of physical restraint" and noted "excited delirium" and PCP intoxication as contributing factors.

NY AG James says on that fateful March day, Prude "was in the throes of a mental health crisis and what he needed was compassion, care, and help from trained professionals. Tragically, he received none of those things."

She adds ... "The criminal justice system has frustrated efforts to hold law enforcement officers accountable for the unjustified killing of unarmed African Americans."

Rochester Mayor Lovely Warren also expressed outrage, saying the grand jury decision is "hard for many of us to understand." She says the City needs to work on policy reform to "correct the inequities in the system."