SUMMARY: Mitt Romney and Rudy Giuliani cite different statistics on Massachusetts crime to make their points.

Rudy Giuliani often ballyhoos his track record reducing crime in New York City. Now he’s going after the track record of his rivals and has former Massachusetts Gov. Mitt Romney in his sights.

“He wasn’t particularly good at reducing crime. ... Murder went up when he was governor. Robbery went up. Violent crimes went up,” Giuliani told the Washington Post on Nov. 24, 2007.

Romney shot back the next day: “The truth of the matter is that during my administration, the FBI’s crime statistics show that violent crime was reduced in Massachusetts by 7 percent. So he’s wrong again on the facts.”

Take apart the FBI crime figures and you’ll see that Romney is right. But Giuliani is also right on a couple of points, bringing to mind Mark Twain’s saying, “There are lies, damn lies, and statistics.” Here’s how the numbers break down:

Romney became governor in January 2003 and left office in January 2007. Comparing FBI crime statistics in Massachusetts for 2002 and 2006, we can calculate how crime rates changed during the Romney administration.

To count violent crime, the FBI includes murder and nonnegligent manslaughter, forcible rape, robbery and aggravated assault. In 2002, that number was 31,137 in Massachusetts. In 2006, it was 28,775. That means violent crime declined 7.6 percent, just like Romney claims. Giuliani is wrong on this point.

But let’s take a closer look at murders and robberies.

Murders went up from 173 in 2002 to 186 in 2006, for an increase of 7.5 percent. The murder rate — the number of people murdered per 100,000 people — moved up from 2.7 to 2.9.

Robberies increased more than murders. Robberies in Massachusetts increased from 7,169 to 8,047, an increase of 12.2 percent. The robbery rate increased from 111.5 to 125.

So what made the violent crime rate go down if murders and robberies went up? The biggest category decline under Romney was aggravated assault, which fell from 22,018 to 18,800, a drop of 14.6 percent.

Given these numbers, Giuliani is right when he says murders and robberies went up, but wrong when he says violent crime went up. So we rate his claim as Half True. And Romney is correct when he says violent crime in Massachusetts declined, so we rate his claim True.