Melissa Drexler, now 20, was slumped in her seat in the courtroom as the judge pronounced sentence, and did not react. The parole laws in operation when Drexler was tried mean that with good behaviour she will serve around three years in jail.
Legal commentators on US Court TV, which broadcast the proceedings live, were unanimous in denouncing the sentence as too lenient. "She got a very good deal, some would call it a sweetheart deal," said one, a qualified judge.
Liberal quarters, however, argued that such cases should not be brought before the criminal court, or if they were, should not automatically attract custodial sentences.
The fact that the judge invoked the 15-year term despite eloquent statements in his summing-up about Drexler's innate goodness, absence of any criminal record and the likelihood that she would never commit a similar crime again was seen as a signal to others who might find themselves in her position. This was stressed afterwards by Elaine Leschot, the prosecutor in the case: "Hopefully, it will act as a deterrent."
Drexler's was one of a spate of infanticide cases in the United States last year. In each, the schoolgirl successfully concealed her pregnancy from her parents and friends, gave birth in secret, and subsequently disposed of the infant.
But it was Drexler's case that shocked Americans most of all, largely because of what was seen as her callousness in returning to the dance- floor immediately after consigning the baby to the rubbish bin.
Ms Leschot recited a series of repellent details from Drexler's admission yesterday - including how she described wrapping the live baby in rubbish bags - to justify her call for a stiff sentence.
Afterwards, she appeared almost to exult that Drexler's ambitions of going to college to study fashion design and then working in New York would now come to nothing.