But prosecutors dropped the felony charges against Michael Perkins, 52, who was released from prison last December after serving nearly 19 years for first-degree robbery, according to officials and records.
The suspect, who also served three years in prison for trying to rob a school in 1990, instead pleaded guilty to petit larceny and was sentenced to just six months in jail in the latest case.
According to police, Perkins — who was held past potential prison release dates in part because of "poor disciplinary history" — allegedly approached the boy and asked to see his cellphone on Aug. 4 just before 3:40 p.m.
The boy handed Perkins his cellphone, but when he asked for it back, the suspect pulled out what appeared to be a box cutter and said "You don't know who you are messing with, just go before I knock you out," according to police.
A couple of straphangers intervened and Perkins was apprehended by police a few blocks from the station.
Police found a bottle opener and crack pipe in Perkins' pocket, they said. Perkins did not have a box cutter, according to the Brooklyn District Attorney's office.
Perkins was originally charged with robbery, grand larceny, menacing, petit larceny, possession of a controlled substance and stolen property, weapons possession and endangering the welfare of a child.
The robbery charge was dropped because the victim voluntarily handed over his phone, the DA's office said.
The DA's office also said it could not defend a grand larceny charge because the phone was valued less than $1,000.
“After the case was arraigned, and upon a further review of the evidence, it was determined that the felony charges could not be sustained,” said Helen Peterson, a spokeswoman for the Brooklyn DA’s office, adding that no plea deals were offered.
The other charges were considered misdemeanors and would have carried the same sentence as petit larceny, up to a year in jail.
Perkins pleaded guilty to petit larceny on Aug. 8, according to the DA's office.
His lawyer, Harvey Herbert, declined comment.