Salvatore Perrone returns to court for a hearing Friday. He has pleaded not guilty to killing the three store owners last year.
His attorney tells the New York Post that a court-ordered psychiatric evaluation found Perrone fit to go to trial.
He faces life in prison on each charge if convicted.
Perrone was indicted in November on three counts of first-degree murder and three counts of second-degree murder. Police say he was spotted in a surveillance footage leaving the scene of the last shooting, on November 16, with a duffel bag.
They said a sawed-off rifle used in the killings was found in the bag. The other murders happened in July and August.
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