Erie County prosecutors announced they will not file charges in connection to the deadly stabbing of a young Baldwin man at the University of Buffalo.

Tyler Lewis, 19, was stabbed to death on Oct. 14 last year on the campus of the University of Buffalo.

Prosecutors say the SUNY Buffalo State sophomore and four friends attempted to buy marijuana from a dealer using counterfeit money.

According to Erie County District Attorney John Flynn, a fight broke out between Lewis and the dealer.

Lewis' friends joined him in beating up the dealer, according to authorities.

News 12 was told that's when the dealer pulled out a knife and stabbed Lewis.

Flynn said in a press conference Friday that evidence shows the stabbing was justified under New York state self-defense laws.

"In addition to the robbery justification that you're allowed to use deadly physical force, if you are being robbed, there's also a second justification, a separate one that says if you are in imminent danger of your life, i.e. being beaten up and stomped on by five individuals, you're also allowed to use deadly physical force. So the stabber here had justification to used deadly physical force,” Flynn said.

During the nearly six month-long investigation, Lewis' family repeatedly called on the DA to make an arrest and to be more transparent.

Last month, the Lewis family also filed a lawsuit against the University of Buffalo and Buffalo State College claiming both failed to adequately screen students with violent histories.

Roquishia Lewis, the late teen’s mother, is devastated by the lack of criminal charges in the case.

“I was shocked, saddened and in disbelief,” she said. “It's not justifiable for anyone to get away with murdering my son.”

Although the Erie County DA has closed the case, his mother says she is going to launch an independent investigation.