He's accused of reclassifying, downgrading and ignoring crimes to make it appear that crime in his jurisdiction was lower than it actually was.
In his first monthly report, sources say he took credit for a sudden and stunning drop in crime.
It was a drop so unbelievable that it sparked a department audit of DiPaolo's numbers here, and at his previous command, the now closed Sixth Precinct in Manhasset.
To their amazement, investigators discovered almost two years of intentional misclassification of 170 specific cases.
Some cases were downgraded from felony to misdemeanor and others were simply uncounted.
In all, Inspector DiPaolo's numbers revealed a 12 percent "error rate" in how cases were classified compared to just two percent across the rest of the county.
"The feeling from our guys on patrol is that crime seems to be peaking up, but the numbers don't reflect it," said James Carver, PBA Chief.
Carver says it's a sign of the pressure top brass has endured in a department slashed to the bone.
"It always makes you wonder, are the reports being generated and calculated they way they should be?" Carver said.
It has been a tough year for the Nassau County Police Department after months of protests against the plan to close half its precincts, consolidating from eight to just four.
DiPaolo, who lost his command when the sixth precinct closed last month, had been transferred to the much busier fifth precinct, which is the next to go.
"We cannot afford to have someone cooking the books," Carver said.
Milagros Vicente lives in the fifth and tried in vain to stop the consolidation plan.
She thinks this is a sign of something bigger.
"They may be pressured to modify the numbers and say crime is down in our area. It makes sense because then they could justify closing our precincts," Vicente said.
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