Tucson's overall violent-crime rate dropped for the second straight year in 2010 despite an increase in homicides, show newly-released data from the FBI.

Reported rape, robbery, aggravated assault, burglary, motor-vehicle theft and arson all decreased in Tucson in 2010, the FBI's preliminary 2010 Uniform Crime Report shows.

Violent crime also decreased nationwide in 2010, show the preliminary data that includes statistics for regions and cities with populations of more than 100,000. The final report, expected to be released sometime this fall, will include data for all Arizona cities and counties.

Here's a closer look at three of the crime categories:

Violent crime

• Tucson's violent-crime rate dropped 3 percent from 2009 and has decreased 34 percent since 2005. That's a steeper decline than in any of nine other Arizona cities with populations of 100,000 or more in that period.

Violent crime includes murder and non-negligent manslaughter, rapes, robberies and aggravated assaults. The rate is calculated by taking the total of those four categories per 100,000 residents.

It's difficult to pinpoint why violent crime has decreased, said Tucson police Sgt. Matt Ronstadt. One thing that may have helped is the violent-crime-reduction initiative launched last summer by the Police Department targeting crime hot spots, events that often lead to violence such as loud parties and violent offenders with outstanding warrants, he said.

"We would love to take credit for reducing the violent-crime rate on our own, but it includes many things beyond us," Ronstadt said. "Ultimately, it's a bit of a guessing game."

Homicide

• After back-to-back years with homicide totals that were abnormally high (65 in 2008) and abnormally low (35 in 2009), the 2010 total for Tucson returned to about average: 51.

From 2002 to 2007, there were between 47 and 55 homicides each year, the FBI data show.

"We don't look at it as an increase - we look at it being back where we typically are," Ronstadtsaid.

Nationwide, homicide dropped by 4 percent from 2009 and has decreased by 13 percent since 2005.

Vehicle theft

• Motor-vehicle thefts declined in Tucson for the fourth consecutive year, following a national trend.

The 3,433 car thefts reported to Tucson police in 2010 were 4 percent less than the 3,564 in 2009 and less than half of the 7,376 reported in 2006. From 2001 to 2008, there were about 6,000 vehicle thefts or more each year, the data show.

The Tucson Police Department has increased its outreach in recent years to teach people how to prevent theft, and new cars have more anti-theft technology every year, Ronstadt said.

The drop in motor-vehicle thefts follows a nationwide trend. Car theft has decreased 41 percent since 2005 nationally, FBI data show.

Contact reporter Brady McCombs at 573-4213 or bmccombs@azstarnet.com