The feds said she used her clout to obtain the bar owners' money, promising them in exchange that she would give them "scanners" to check the IDs of their patrons.
The scanners were either never delivered or delivered then later collected, authorities said.
Kepler pleaded guilty in June to nine counts of extortion, three days after her trial had started and the government had rested its case.
Dalzell said Kepler's criminality was "corrosive," adding that it was important to "deter law enforcement from abusing their power" and ensure that they are honest. "This is not a kleptocracy," he said.
During the trial, several bar owners testified that they feared that Kepler would shut down their establishments if they did not give her money.
Defense attorney William R. Spade, Jr. said Kepler had paid back $2,000 to two bar owners before being indicted.
Spade said Kepler had no criminal history, helped educate youth and received satisfactory work reviews before being suspended in February 2009.
Kepler, who has lost her state pension, was a liquor-controlenforcement officer from July 2000 until her resignation in May 2009.
Assistant U.S. Attorney Arlene Fisk said Kepler had been investigated for alleged involvement in other scams. "There is simply no stopping this defendant," she said, adding: "The fact that she used her official position to take money is particularly heinous."
Prosecutors said they still don't know what Kepler did with the money she got from bar owners.
But Fisk said in her sentencing memo that Kepler had amassed more than $80,000 in gambling losses, according to Atlantic City casino records.