A homeless man will serve up to five years in prison for jumping into a cab last year, robbing its passenger of her smart phone, and then slamming her friend’s face into the pavement after demanding money to get it back, Suffolk County District Attorney Daniel F. Conley said today.

GERALD HAMILTON (D.O.B. 2/10/66), who has no fixed address, pleaded guilty yesterday as his trial was set to begin on charges of unarmed robbery and assault and battery with a dangerous weapon. Suffolk Superior Court Judge Christine McEvoy sentenced him to 4 to 5 years in state prison followed by 18 months of probation upon his release. She further ordered Hamilton to undergo drug treatment and to stay away from the victims.

Had the case proceeded to trial, Assistant District Attorney Montez Haywood of Conley’s Major Felony Bureau would have told jurors that, in the early morning hours of Nov. 13, 2010, Boston Police were called to 25 Stuart St., where a 23-year-old Allston woman had been robbed and her friend, a 20-year-old Cambridge resident, was suffering from a bloody gash to her face and a swollen eye.

Haywood would have proven that the victims were in a taxi at about 3:30 a.m. when Hamilton opened the door to their cab and got inside. He grabbed unsuccessfully at the Allston woman’s purse before snatching her BlackBerry Torch and jumping out of the cab.

Evidence would have established that the two women got out of the cab and the cell phone’s owner pleaded with Hamilton to return the phone. Hamilton ordered her to go to the Citibank kiosk across the street and withdraw $40 to get her phone back. The 20-year-old stayed behind on the street while the other victim went to the cash machine. At some point, the victim tried to grab her friend’s phone from the defendant’s hand, and Hamilton pushed her to the ground and slammed her face on the sidewalk. The defendant then ran across the street to the ATM kiosk, took the money from the first victim, and returned her phone before fleeing the scene.

Hamilton’s identity was unknown to the victims or Boston Police, and they had only a general description of him, Haywood would have shown. Boston Police detectives were able to obtain surveillance images from the bank, however, and provided them to the Boston Regional Intelligence Center of the Boston Police Department. The BRIC distributed the images internally, and multiple officers familiar with Hamilton identified him within hours. Detectives obtained a warrant for Hamilton’s arrest later the same day and apprehended him about a month later – at the very same Stuart Street location where the robbery had occurred.

Michael Coffey was the DA’s assigned victim-witness advocate. Hamilton was represented by attorneys Kevin Ruderman and Arnie Stewart.