First, said investigators, he left his cats with a friend for safekeeping. Then, he gave the keys to his apartment back to the landlord with the strange comments that "everything will be resolved on Friday" and "I won't be back."
Those actions by Empire State Building killer Jeffrey Johnson have led a number of law enforcement experts to suspect that Johnson was a man on his way to committing "suicide by cop" when he was gunned down by officers Friday.
"I think it is a pretty strong case, especially with the artifacts he left before the fact," Eugene O'Donnell, a professor of police science and criminal law at John Jay College, said.
NYPD spokesman Paul Browne didn't want to speculate about what Johnson's intention may have been regarding suicide. Clearly, he wanted to provoke police, said Browne.
"He gave officers no alternative but to shoot," said Browne.
Moments before he was shot dead on Fifth Avenue, Johnson, who a year ago lost his job as a fashion designer, had used a .45-caliber handgun to kill former colleague Steven Ercolino. Johnson then walked around the corner to the front of the iconic building, where he drew his weapon again -- only to be shot by two police officers when he aimed his gun toward them.
Johnson, 58, could have walked to the west, away from Fifth Avenue and the police counterterrorism post at the Empire State Building, possibly eluding capture, O'Donnell said.
"He must have known that the path he took, east and north, he knew that he was virtually walking into the hands of police," O'Donnell said.
"The guy had no intent on coming back," said Joe Giacalone, an adjunct professor of police tactics at John Jay. "He had every intention of ending his life himself or getting stopped by the cops and taking out his gun and have them shoot."
"Suicide by cop" is defined as a person's willingness to cause his or her own death by confronting law enforcement to such a degree that it compels an officer to act with deadly force, said Rebecca Stincelli, a victim-trauma expert who has studied the phenomenon and testifies about it in court.
"I can only speculate about this guy," Stincelli said.
Stincelli said Johnson may have been suicidal and may have planned to kill himself at some point.
"It could have been spontaneous, that he changed his mind and raised his gun [at] police officers," said Stincelli, who estimates that about 10 percent to 12 percent of police shootings involve people who want to die.
Ercolino's family and friends Monday mourned his loss during his wake in White Plains.
His wake continues Tuesday evening. The funeral is at 11 a.m. Wednesday at Our Lady of Sorrows Church in White Plains.