Jurors began deliberating Thursday in the trial of Randy Santos, a 31-year-old man who fatally beat four homeless men as they slept on New York City streets in October 2019, according to court proceedings.

Santos was arrested with a bloody metal bar in his hands shortly after the rampage that killed four men in Chinatown, prosecutors said. The victims — Chuen Kok, Anthony Manson, Florencio Moran and Nazario Vásquez Villegas — ranged in age from 39 to 83, according to court records.

Santos has pleaded not guilty to murder charges in their deaths and to attempted murder and assault charges involving other men in the hours and days before the killings. His defense team acknowledges he committed the acts but argues he was too mentally ill to be held criminally responsible.

The Dominican-born Santos had been diagnosed with schizophrenia, according to his attorneys. Defense attorney Arnold Levine argued in closing statements Wednesday that Santos sincerely believed he heard voices telling him he had to kill 40 people or would die himself.

“The only explanation was Randy’s psychosis. … It’s the only thing that explains what happened,” Levine told jurors, according to court testimony. The defense attorney contended that while Santos might have recognized he could face legal trouble, he couldn’t appreciate that his actions were morally wrong due to his mental illness.

“Psychosis replaced Randy’s moral judgment,” Levine said during his closing argument.

Prosecutors disputed the insanity defense, arguing that Santos understood both the illegality and immorality of his actions. Manhattan Assistant District Attorney Alfred Peterson emphasized that Santos sometimes looked out for potential witnesses during the attacks and told a psychiatrist in 2024: “I know it’s not a good action.”

“Despite his illness, he was able to make a determination that what he was doing was wrong,” Peterson said in his summation Wednesday.

Santos, who has been following the trial through a Spanish-language interpreter, listened without showing much reaction to the closing arguments, according to courtroom observers. At one point, he briefly fluttered his hands near his face as his attorney described delusional episodes that occurred before the Chinatown killings, including an incident where Santos lashed out at his grandfather.

The October 2019 attacks brought renewed scrutiny to the city’s efforts to aid and protect its homeless population, which had reached record size at the time. Santos was homeless when the killings occurred, as were some of his victims.

The case presents jurors with two starkly different outcomes. If they reject Santos’ insanity defense and convict him of murder, he could face life in prison. However, if jurors find him not responsible by reason of mental disease or defect, Santos could be involuntarily committed to psychiatric treatment for as long as officials and a court determine necessary.

The deliberations mark the culmination of a trial that has examined the intersection of mental illness, homelessness, and violent crime in New York City. The case has highlighted ongoing challenges facing the city’s most vulnerable residents and the systems designed to protect them.

The jury must now weigh the evidence and expert testimony to determine whether Santos’ diagnosed mental illness prevented him from understanding the moral wrongness of his actions during the deadly October 2019 rampage that shook the Chinatown community.