Prosecutors said Rivera committed "an unprovoked and violent series of stabbings" that killed three.
"These fatal stabbings have shaken our city, and those who commit random acts of violence will face accountability," said Manhattan DA Alvin Bragg.
Rivera allegedly broke into a hardware store on 1st Av November 18, emerging with a stolen backpack and stolen kitchen knives that he used to stab a construction worker, Angel Landi, a man fishing, Chang Wang, and a woman sitting on a park bench, Wilma Augustin.
Ramon Rivera, 51, confessed to the killings during questioning, according to police sources.
His case renewed frustration with the city's inability to treat people in mental distress and hold people with a history of low-level criminal activity.
Rivera's eight prior arrests in New York City mainly involved shoplifting. None involved a weapon.
He has been arrested at least nine times in the past year in New York and New Jersey and was out without bail pending trial on his most recent arrests.
Rivera lived at the Bellevue Men's Shelter, but also gave prior addresses of University Avenue in the Bronx and in Kissimmee, Florida.
He had two documented interactions with the city while in mental distress:
- Nov. 19, 2023 -lying on curb in Flushing, Queens, acting erratically and complaining of left arm pain.
- Dec. 2023 -- calling 911 in Brooklyn claiming he was suicidal and someone wanted to kill him. He was taken to Woodhull Hospital in Brooklyn for treatment.
Also in December 2023, he stole steaks from a supermarket in the Bronx, followed by four other incidents of breaking into Manhattan stores to steal cigarettes, lighters and vapes.
Rivera was held in jail from February 19 to October 17. While in custody, on May 7, he assaulted a police officer and an emergency medical worker at the Bellevue hospital psych ward.
Upon release, he was charged with grand larceny for stealing a $1,495 acrylic bowl from the Jonathan Adler store at 382 West Broadway in Soho. Prosecutors asked for bail but the judge released him.
Mayor Eric Adams said after the arrest that he has been pushing for the power to involuntarily remove people with mental health challenges from the streets.
"This is the failure of our unwillingness to face the problem, address the problem," Adams said. "Each time we implement these long-term, successful ways of addressing these issues, we have a pushback by a host of people who will not allow us."
He said this is the result of not taking action and ignoring people who need help.
"You're seeing it on the subway, you're seeing it when you walk the streets, you probably see it in your neighborhood, people talking to themselves, yelling at themselves, walking around with no shoes on in 20 degree weather," Adams said.
He said legislation strengthening the power to involuntarily remove troubled homeless people from the streets will be a priority in Albany next session.
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